Your home equity and current mortgage rate decide the best ADU financing route for most U.S. homeowners. If you have a notably low first mortgage rate, refinancing to fund an ADU will generally cost you far more each month than tapping equity with a HELOC or home equity loan. If you have little equity but strong credit, renovation mortgages like Fannie Mae HomeStyle Renovation or Freddie Mac CHOICERenovation can underwrite to the property’s after-completed value, expanding your borrowing power before a single board is nailed. And before you commit to any loan, check whether your state or city offers a grant or zero-interest program first.
Run these three checks right now:
- Your current mortgage rate vs. today’s market rate. If your rate is meaningfully below current market rates, preserve it. A HELOC or home equity loan lets you borrow against equity without touching the first mortgage.
- Your loan-to-value ratio and available equity. Most equity-based products require at least 15–20% remaining equity after the new loan. If you’re close to that floor, a renovation mortgage underwritten to after-improved value may unlock more capital.
- Whether a local or state ADU program applies. The CalHFA ADU Grant Program reimburses up to $40,000 in predevelopment costs for eligible low-income California homeowners. MassHousing’s ADULP and New York City’s Plus One ADU Program offer similar structures in their markets. Free or low-cost money always beats borrowed money.
Pro Tip: Search your state housing finance agency (HFA) website before you call a lender. Grant and deferred-loan programs often close when funds run out, and many have application windows that open only once or twice a year.
Table of Contents
- What are the main ADU financing options for homeowners?
- Are there state and municipal ADU grant programs worth checking first?
- How do Fannie Mae HomeStyle and Freddie Mac CHOICERenovation work for ADUs?
- Can projected ADU rental income help you qualify for a loan?
- What do lenders and programs require to approve ADU financing?
- How long does ADU financing actually take?
- What does an ADU actually cost, and how does the math work?
- What are the real risks of borrowing to build an ADU?
- How do you choose the right ADU financing route for your situation?
- What should you do in the next 30 and 90 days?
- Key Takeaways
- The financing decision most homeowners get backwards
- Live Large™ makes the ADU financing and build process simpler
- Useful sources for further research
What are the main ADU financing options for homeowners?
Seven loan types cover nearly every homeowner situation. Here’s how they stack up.
- HELOC (Home Equity Line of Credit). A revolving credit line secured by your home equity. Rates are variable, draws are flexible, and you only pay interest on what you use. Best when construction costs are uncertain or phased.
- Home equity loan (second mortgage). A lump-sum loan at a fixed rate, also secured by equity. Predictable payments, but you borrow the full amount upfront whether you need it yet or not.
- Cash-out refinance. Replaces your existing mortgage with a larger one and gives you the difference in cash. Makes sense only if today’s rates are close to or below your current rate. Touching a 2–3% mortgage to fund an ADU is almost always a losing trade.
- Construction-to-permanent loan. Covers the build phase, then converts to a standard mortgage at completion. Underwritten to post-construction value, which matters when current equity is thin. Expect higher credit score requirements (commonly 680–720+) and a longer approval process.
- Renovation mortgages (Fannie Mae HomeStyle, Freddie Mac CHOICERenovation, FHA 203(k)). These let you finance construction based on the property’s as-completed value rather than today’s value. Particularly useful for homeowners who need to borrow more than current equity supports.
- Unsecured personal loans / credit cards. Fast to fund, no equity required, but rates are significantly higher. Reasonable only for small gap financing or short-term bridge needs, not a $150,000 ADU build.
| Loan Type | Borrowing Basis | Rate Type | Touches First Mortgage? | Typical Credit Score |
|---|---|---|---|---|
| HELOC | Current equity | Variable | No | 620–680+ |
| Home equity loan | Current equity | Fixed | No | 620–680+ |
| Cash-out refinance | Current equity | Fixed | Yes | 620+ |
| Construction-to-perm | Post-construction value | Fixed | Often yes | 680–720+ |
| HomeStyle / CHOICERenovation | As-completed value | Fixed | Often yes | 680+ |
| FHA 203(k) | As-completed value | Fixed | Yes | 580–620+ |
| Personal loan | Unsecured | Fixed (high) | No | 680+ |
The key dividing line is whether a product borrows to current value or after-improved value. Fannie Mae HomeStyle, Freddie Mac CHOICERenovation, and most construction loans use the latter, which can unlock substantially more capital for homeowners who haven’t yet built the equity that the ADU itself will create.
Are there state and municipal ADU grant programs worth checking first?
Yes, and they’re often the most underused tool in the financing stack. Municipal and state programs typically come in four structures: forgivable loans, deferred-repayment loans, zero-interest loans, and reimbursement grants for predevelopment costs. The catch is that most require you to have finalized architectural plans, permits, and sometimes contractor bids before you can even apply.
Three programs every homeowner should know:
- MassHousing Accessory Dwelling Unit Loan Program (ADULP). Targets income-qualified Massachusetts homeowners with below-market financing for ADU construction or conversion. Requires finalized plans and permits before application, per MassHousing program guidance. Income caps and loan limits apply.
- New York City Plus One ADU Program. Open to owner-occupants of single-family detached homes with household income below 165% of Area Median Income (AMI). The program provides low-interest HPD loans up to $220,000 per borrower, plus New York State HCR construction financing grants up to $175,000 per grantee. The interest rate starts at 5% and can be reduced to as low as 0% based on affordability underwriting. Loan terms run up to 15 years, extendable to 30. Borrowers who receive deferred-forgivable loans must agree to rent-restrict the ADU at 100% AMI for 15 years from project completion.
- CalHFA ADU Grant Program. Reimburses eligible low-income California homeowners for predevelopment costs (permits, design, soil tests) up to $40,000. Many municipal grant programs are reimbursement-based, meaning you front the costs and get paid back, so plan for bridge cash or a small personal loan to cover early expenses.
What to prepare before applying to any public program:
- Proof of income and AMI eligibility documentation
- Certified site plan and architectural drawings
- Permit application or issued permit
- Contractor bids from licensed contractors
- Proof of current mortgage and homeowner insurance
- Municipal tax and utility payment status (required for NYC Plus One)
To find programs in your area, check your local housing authority, your state’s HFA website, and your municipal planning department. The ADU guides and resources at A-du also aggregate municipal program summaries by state.
Pro Tip: Many grant programs are reimbursement-based and require you to front predevelopment costs. Secure a small personal loan or use savings to cover architect fees and permit costs before applying, so you’re not stuck waiting for reimbursement to start the clock.
How do Fannie Mae HomeStyle and Freddie Mac CHOICERenovation work for ADUs?
Both products let you borrow based on the property’s as-completed appraised value rather than what it’s worth today. That distinction matters enormously when you’re building a detached ADU that will add $150,000 to your property’s value but you only have $80,000 in current equity.
Fannie Mae HomeStyle Renovation and Freddie Mac CHOICERenovation treat ADUs as a standard home feature and allow financing across purchase, refinance, and renovation loan types. Both products are available through conventional lenders, which means competitive rates and broad availability.
How the process works, step by step:
- Define the project scope. Get detailed contractor bids and a construction timeline. Lenders require certified blueprints, licensed contractor documentation, and a cost breakdown before ordering the appraisal.
- Order an as-completed appraisal. The appraiser values the property as if the ADU were already built, using comparable sales of properties with ADUs. This is the number that determines your maximum loan amount.
- Underwriting review. Lenders typically require a credit score of 680+ for renovation mortgages, along with standard income and DTI documentation. Construction and renovation loans are underwritten as development projects, so expect more documentation than a standard refinance.
- Loan closes; funds go into escrow. Renovation funds are held in a controlled account and released in draws as construction milestones are completed and inspected.
- Construction completes; loan converts or remains. For purchase or refinance structures, the loan is already permanent. For construction-to-perm products, it converts at certificate of occupancy.
Renovation mortgages vs. HELOCs and construction loans:
- Borrowing power: Renovation mortgages win when current equity is limited, because they underwrite to after-improved value.
- Rate: Renovation mortgages typically carry rates close to standard mortgage rates. HELOCs are variable and currently higher; construction loans often carry a rate premium during the build phase.
- Closing costs: Renovation mortgages involve full closing costs, similar to a refinance. HELOCs have lower upfront costs.
- Complexity: Renovation mortgages require more documentation and a longer approval timeline (4–8 weeks or more) than a HELOC (2–6 weeks).
Pro Tip: Ask your lender upfront whether they have in-house experience with HomeStyle or CHOICERenovation for ADU projects specifically. Many lenders offer these products on paper but rarely process them for ADUs, which slows everything down.
Can projected ADU rental income help you qualify for a loan?
Often yes, and it can move the needle on loan size more than most homeowners expect. Many lenders, particularly those using Fannie Mae or Freddie Mac guidelines, will allow up to 75% of projected rental income to count toward your qualifying income when it’s documented by a signed lease or a rent appraisal.
Here’s a simplified example of how that plays out in a DTI calculation:
| Scenario | Monthly Gross Income | Projected ADU Rent | 75% Inclusion | Effective Income for DTI |
|---|---|---|---|---|
| With documented ADU rent | — | — | $1,500 | — |
That $1,500 increase in qualifying income can translate to a meaningfully higher loan limit, depending on your existing debt load. For a borrower with $3,000 in monthly debt obligations, the DTI drops from 37.5% to 31.6% with the rental income included, which can push them into a better rate tier or over a program eligibility threshold.
What documentation lenders typically require:
- A signed lease agreement from a tenant (for existing ADUs)
- A rent comparables appraisal or market rent analysis (for new ADUs not yet leased)
- Property operating projections for the ADU unit
- Confirmation that the ADU is a legal, permitted unit
Where this works and where it doesn’t:
Fannie Mae and Freddie Mac programs are the most likely to accept projected rental income with proper documentation. Portfolio lenders (banks that hold loans on their own books) vary widely. FHA 203(k) and most HELOC products typically do not count projected rent from an ADU that isn’t yet built. The earlier you document projected rent in the underwriting process, the smoother the qualification goes. Counting projected ADU rent can materially increase loan eligibility, but many lenders require a signed lease or detailed rent appraisal, so plan to document that rent early. For a deeper look at how rental income affects your numbers, the ADU rental income potential guide walks through the math in detail.
What do lenders and programs require to approve ADU financing?
Lenders treat ADU projects as development projects, not simple home improvements. That means the documentation bar is higher than a standard refinance or HELOC, and missing one item can stall underwriting by weeks.
Typical financial thresholds by product:
- HELOC / home equity loan: Credit score of 620–680+, combined LTV typically capped at 80–85% of current value, DTI generally below 43–45%.
- Construction-to-permanent / renovation mortgages: Credit score of 680–720+ commonly required; lenders want to see stable income history and a DTI that accounts for the new loan payment plus existing obligations.
- Municipal grant programs: Income documentation to verify AMI eligibility; some programs have minimum credit score requirements as well.
Project documentation checklist:
- Certified architectural blueprints and site plan
- Issued building permit or permit application with fee payment confirmation
- Contractor bids from licensed, insured contractors (at least two bids is standard practice)
- Licensed contractor credentials and insurance certificates
- Construction timeline with milestone schedule
- Contingency plan (most lenders want to see a 10–15% cost contingency built into the budget)
- Property appraisal (as-completed for renovation/construction loans)
Public program quirks:
Many municipal grant programs require finalized predevelopment materials before you can submit an application. That means you may need to spend $5,000–$15,000 on architectural plans and permit fees before you know whether you’re approved. Securing a small personal loan or using savings to cover these early costs is often the practical path. The ADU floor plans guide explains what lenders and programs typically expect in terms of plan detail and scope.
Pro Tip: Organize your underwriting package in this order: (1) property appraisal or as-completed appraisal, (2) contractor bid with line-item cost breakdown, (3) permits and blueprints, (4) income documentation including projected rent appraisal. Underwriters typically pull these in that sequence, and having them ready in order cuts review time.
How long does ADU financing actually take?
Timeline varies significantly by product, and the delays almost always come from the same three sources: incomplete project documentation, appraisal scheduling, and municipal review backlogs.
| Financing Route | Typical Approval to Funding | Common Delay Risks |
|---|---|---|
| HELOC / home equity loan | 2–6 weeks | Appraisal scheduling, title review |
| Cash-out refinance | 30–45 days | Rate lock timing, title, appraisal |
| Construction-to-perm loan | 4–8+ weeks | Incomplete plans, contractor docs, appraisal |
| HomeStyle / CHOICERenovation | 4–8+ weeks | As-completed appraisal, contractor licensing |
| Municipal grant programs | Varies widely | Application windows, plan review, income verification |
Construction loans add a layer of ongoing coordination that other products don’t. Funds are released in stages tied to construction milestones, and each draw requires a lender inspection to confirm the work is complete before the next disbursement goes out. A contractor who misses a milestone or submits incomplete invoices can stall the entire draw schedule and delay the project.
Common delay risks to plan for:
- Incomplete architectural plans or missing permit documentation at application
- Contractor documentation gaps (missing license, insurance, or bid detail)
- Appraisal scheduling backlogs, particularly in high-demand markets
- Municipal plan review delays for permit issuance
- Income verification complexity when self-employed or using projected rental income
Practical steps to shorten your timeline:
- Pre-apply to local grant programs before lender shopping, since program windows can close
- Get contractor bids and certified plans in hand before you approach lenders
- Schedule the appraisal as early as the lender allows
- Ask lenders about their draw inspection process and turnaround time before committing
What does an ADU actually cost, and how does the math work?
ADU projects commonly cost from roughly $40,000 for a simple garage or basement conversion up to $400,000 or more for a detached new build with full utility hookups and site work. The wide range reflects real variables: foundation type, utility connections, local labor costs, and whether you’re converting existing space or building from scratch.
Three worked financing scenarios:
-
High-equity homeowner using a HELOC. Home value: $600,000. Existing mortgage: $250,000. Available equity at 80% LTV: $230,000. ADU budget: $150,000. A HELOC at a variable rate covers the build in flexible draws, preserves the existing low first mortgage, and leaves equity headroom. Monthly interest-only payments during construction keep cash flow manageable.
-
Low-equity homeowner using a renovation mortgage. Home value: $450,000. Existing mortgage: $360,000. Current equity is too thin for a HELOC. As-completed appraisal values the property at $580,000 after ADU construction. A HomeStyle Renovation mortgage underwrites to that $580,000 figure, unlocking enough capital to fund the $120,000 build. Without the as-completed appraisal, this homeowner couldn’t finance the project at all.
-
Homeowner using projected rental income to qualify. Same homeowner as scenario 2. Projected ADU rent: $1,800/month. At 75% inclusion, $1,350/month counts toward qualifying income. That addition drops DTI from 44% to 37%, pushing the borrower into standard underwriting territory. For more on how these ADU investment returns play out over time, the numbers are worth reviewing before you finalize your loan size.
Interest rate and fee comparison (approximate ranges):
HELOCs currently run variable, often tracking the prime rate with a margin. Cash-out refinances and renovation mortgages carry rates close to standard 30-year fixed mortgage rates, though renovation products sometimes carry a small premium. Construction loans often have higher rates during the build phase, then convert to permanent financing at a lower rate. Personal loans carry the highest rates of any option, often well above 10%.
Tax considerations:
Interest on home equity loans and HELOCs used to build or substantially improve a primary residence is generally deductible under IRS rules for qualified residence interest, subject to loan limits. A cash-out refinance used for ADU construction may also qualify. Property tax reassessment is a real consideration: adding an ADU typically triggers a reassessment of the property’s value, which increases your annual tax bill. The timing and magnitude vary by jurisdiction. Consult a tax professional before finalizing your loan structure.
What are the real risks of borrowing to build an ADU?
The biggest risk most homeowners underestimate is cost overrun. ADU construction budgets routinely run 10–20% over initial estimates, and if your loan is sized exactly to the bid, you’ll be scrambling for gap financing mid-project.
Common downsides by loan type:
- HELOC: Variable rate means payments can rise during a long construction period. If the project stalls, you’re paying interest on drawn funds with no rental income yet.
- Cash-out refinance: Permanently raises your first mortgage rate and balance. If you hold a sub-4% mortgage, this is a costly trade.
- Construction loans: Draw schedule delays can cascade. One missed inspection stalls the next disbursement, which can delay contractor payments and slow the build.
- Municipal reimbursement grants: Require cash reserves upfront. If you don’t have liquidity to front predevelopment costs, you can’t access the grant.
Red flags to watch for:
- Contractors who won’t provide itemized bids or resist fixed-price contracts
- No contingency line in the construction budget (10–15% minimum is standard)
- Counting projected rental income without a signed lease or formal rent appraisal
- Equity cushions below 15–20% after the new loan closes
- Home Equity Investment (HEI) products marketed as “no-payment” options. The CFPB has flagged that these equity-sharing contracts transfer a portion of future home appreciation to an investor and can be more expensive long-term than conventional borrowing.
Risk mitigation that actually works:
Fixed-price contracts with licensed contractors eliminate the most common source of budget blowout. Lender escrow protections on draw schedules prevent funds from being released before work is verified. A 10–15% contingency reserve built into the loan amount gives you room to absorb surprises without stopping construction.
Non-obvious costs to budget for:
Permit and impact fees, utility hookup charges (especially for detached ADUs requiring new water and sewer connections), and temporary housing or lost rental income during construction can add $10,000–$30,000 or more to the true project cost. These rarely appear in contractor bids.
Pro Tip: Get a fixed-price contract before you finalize your loan amount. Variable-cost contracts shift all overrun risk to you, and lenders won’t increase a construction loan mid-project without significant documentation and delay.
How do you choose the right ADU financing route for your situation?
Match your profile to the right starting point, then pursue two paths in parallel: the loan product that fits your equity and rate situation, and any municipal or state grant program you might qualify for.
Profile-driven decision prompts:
- You have a low mortgage rate (below 5%) and sufficient equity. Start with a HELOC or home equity loan. You preserve the first mortgage, draw funds flexibly, and avoid refinancing costs. First document to assemble: recent mortgage statement showing current rate and balance.
- You have high equity and today’s rates are close to your existing rate. A cash-out refinance simplifies the structure into one loan. First document: mortgage statement plus a current rate quote from two lenders.
- You have low equity or need to borrow more than current equity supports. A renovation mortgage (HomeStyle or CHOICERenovation) or construction-to-perm loan underwritten to after-improved value is your path. First document: contractor bid and certified site plan for the as-completed appraisal.
- You’re income-qualified and in a state or city with ADU programs. Apply for grants or low-interest loans through MassHousing ADULP, NYC Plus One, CalHFA, or your local equivalent before committing to market-rate borrowing. First document: income documentation for AMI eligibility verification.
The one question to ask every lender:
“Will you underwrite to after-improved value, and will you accept projected rental income with a lease or rent appraisal?”
A lender who answers yes to both opens up significantly more financing options. A lender who answers no to both is limited to current-value equity products.
The parallel path principle:
Don’t wait to finish lender shopping before checking municipal programs. Grant application windows close, and the predevelopment work required to apply (plans, permits, bids) is the same work lenders need anyway. Starting both tracks simultaneously saves weeks. For a broader look at ADU financing alternatives, comparing lending sources before you commit is worth the time.
What should you do in the next 30 and 90 days?
30-day checklist:
- Pull your mortgage statement and note your current rate, balance, and remaining term.
- Pull your credit report from AnnualCreditReport.com and check your score with your bank or credit card issuer.
- Estimate your current LTV: divide your mortgage balance by your home’s estimated value.
- Get two contractor bids for your ADU concept (even rough bids help lenders and programs assess scope).
- Research local ADU grant programs through your city’s housing authority and state HFA website. Note application deadlines.
- Pre-qualify with one or two lenders who have ADU experience. Ask the after-improved-value question upfront.
90-day checklist:
- Finalize architectural plans and submit permit applications.
- Submit municipal grant applications if you’re eligible, with all required predevelopment documentation.
- Lock a contractor with a fixed-price contract that includes a 10–15% contingency.
- Schedule the as-completed appraisal with your lender as early as the process allows.
- Complete lender underwriting, including income documentation and projected rent appraisal if applicable.
First three professionals to contact:
- Your local housing authority or state HFA (to check grant eligibility and application windows)
- An ADU-experienced lender or mortgage broker (to assess equity, rate tradeoffs, and product fit)
- A licensed contractor with ADU project experience (to produce the certified bids and timeline lenders require)
Documents to gather now:
Most recent mortgage statement, homeowner insurance declarations page, two years of tax returns, recent pay stubs or income documentation, preliminary contractor bid, and any existing site plans or permit pre-application materials.
Key Takeaways
Your home equity and current mortgage rate are the two factors that determine which ADU financing route to pursue first, and checking local grant programs before borrowing can save tens of thousands of dollars.
| Point | Details |
|---|---|
| Equity and rate decide the route | If your mortgage rate is below market, use a HELOC or home equity loan to preserve it rather than refinancing. |
| Renovation mortgages unlock more capital | Fannie Mae HomeStyle and Freddie Mac CHOICERenovation underwrite to as-completed value, helping low-equity homeowners borrow more. |
| Grants come first | Programs like CalHFA (up to $40,000), MassHousing ADULP, and NYC Plus One offer low-cost or free capital before you borrow at market rates. |
| Rental income can boost your qualifying power | Up to 75% of projected ADU rent can count toward income with a signed lease or rent appraisal, lowering your effective DTI. |
| Live Large™ helps you package and execute | Live Large™ supports homeowners with underwriting documentation, HELOC guidance, contractor coordination, and turnkey ADU construction. |
The financing decision most homeowners get backwards
Most homeowners start by calling a lender. The smarter move is to start by checking what your city or state will give you for free or near-free, then figure out what you need to borrow on top of that. The grant programs that exist, from CalHFA’s predevelopment reimbursements to NYC Plus One’s forgivable loan structure, were designed specifically for this moment, and most homeowners who qualify never apply because they didn’t know the programs existed or assumed the paperwork was too complex.
The second mistake is treating the HELOC vs. refinance question as a simple math problem. It’s not. The right answer depends on your rate, your timeline, how much equity you need, and whether you plan to sell in the next five years. A homeowner who refinances out of a 2.75% mortgage to fund an ADU at today’s rates will pay that rate premium for the life of the loan, even after the ADU is generating rent. The incremental monthly cost of that decision, compounded over 20 years, often exceeds the total cost of the ADU itself.
The third thing worth saying plainly: ADU construction is a development project, not a home improvement. Lenders who specialize in ADUs will tell you that the documentation bar is closer to a commercial construction loan than a kitchen remodel. Homeowners who walk into underwriting with a rough estimate and a handshake agreement with a contractor lose weeks. Those who arrive with certified plans, two licensed contractor bids, a construction timeline, and a rent appraisal, close faster and often qualify for better terms.
The financing decision and the construction decision are not sequential. They run in parallel, and the documents that unlock financing are the same documents that define the build. Start both tracks on day one.
Live Large™ makes the ADU financing and build process simpler
Pulling together the documentation that lenders and grant programs require is one of the most time-consuming parts of financing an ADU, and it’s where most projects stall before they start. Live Large™ handles that work as part of its turnkey ADU service.
When you work with Live Large™, you get help assembling the underwriting package your lender needs: contractor bids, certified plans, construction timelines, and the project documentation that municipal programs require before they’ll accept an application. The team advises on HELOC vs. refinance tradeoffs based on your specific mortgage situation, coordinates draw schedules with contractors to keep construction moving, and can point you toward local and state grant programs worth applying for before you borrow. From design and permitting through construction and installation, the entire process is managed under one roof. If you’re exploring an adaptive reuse ADU or a detached backyard build, Live Large™ covers both. To understand exactly what the turnkey process looks like from first conversation to move-in, the ADU turnkey development guide walks through every step. Get in touch to discuss your project and get a consultation scheduled.
Useful sources for further research
The programs and guidelines below are worth bookmarking as you move through the financing process.
- Fannie Mae ADU Guidance — Authoritative source for HomeStyle Renovation eligibility, as-completed value underwriting rules, and rental income treatment. Use this when reviewing what your lender can and can’t do under Fannie guidelines.
- MassHousing ADULP — Program rules, income limits, and application requirements for Massachusetts homeowners. Check here for current loan limits and documentation requirements before applying.
- CalHFA ADU Grant Program — California’s predevelopment cost reimbursement program. Covers eligibility criteria, income limits, and the reimbursement process for permits, design, and soil testing costs up to $40,000.
- NYC Plus One ADU Program (HPD) — Full term sheet for New York City’s program, including loan amounts, interest rate structure, AMI eligibility, and regulatory agreement requirements.
- NerdWallet ADU Financing Guide — Practical overview of loan types and the keep-rate-vs-refinance decision framework. Good starting point for comparing options before lender conversations.
- RenoFi ADU Financing Guide — Detailed breakdown of renovation loan products, credit score requirements, and underwriting expectations for ADU construction projects.
- A-du ADU Guides & Resources — Aggregates municipal program summaries and ADU regulation guides by state. Useful for finding local programs beyond the major state HFAs.
For city and county programs not listed above, search “[your city/county] ADU grant program” or “[your state] housing finance agency ADU” and check the municipal planning department’s website directly. Program availability and funding levels change frequently.