How Contractor Progress Payments Should Work in California

The Deposit Trap: How ADU Homeowners Lose Money Before Work Begins

A $19,500 deposit on an ADU project sounds like a lot of money — and under California law, it's 19 times too much. An NBC Bay Area investigation found one ADU builder collected exactly that amount up front, then refunded it only after reporters started asking questions. Another homeowner, Eileen Horton, reported losing $30,000 to a different ADU builder accused of oversized down payments and stalled work.

The law here is unambiguous. On any home improvement contract over $500, a contractor may take a down payment of no more than $1,000 or 10% of the contract price, whichever is less. Contractors also may not request or accept payment that exceeds the value of work performed or materials actually delivered to your property, according to contractor payment guidance citing Business & Professions Code §7159. Violating the deposit cap is a misdemeanor carrying a $100–$5,000 fine, up to a year in county jail, and CSLB discipline.

Date-based payment schedules are the other trap. A contract demanding "$10,000 every two weeks" is not a progress payment schedule — it's an unsecured loan to your contractor, made with your money, at zero interest, with your house as the only collateral. If the builder walks, files bankruptcy, or simply stops showing up, you're an unsecured creditor trying to claw funds back.

So why does this keep happening in the ADU space? A few reasons stand out:

• ADU demand surged faster than the pool of experienced builders, drawing in companies with thin construction track records but polished sales funnels.
• Builders use paperwork loopholes — one investigated company relabeled its contract a "preconstruction service agreement" and called the homeowner an "owner builder" to dodge the deposit cap.
• Homeowners often don't know the cap exists, so a five-figure "deposit to order materials" doesn't raise alarms.
• A subcontractor on the investigated project claimed he was owed roughly $55,000 in unpaid foundation work — a sign the builder was using one customer's deposits to fund another's job.

The documented cases show how quickly this compounds. In one case study, a homeowner paid $16,800 up front on a $28,000 contract — 60% of the price against a $1,000 legal cap — and the job was abandoned at roughly 60% complete with about $24,000 paid, under an expired plumbing license and no electrical permit.

The pattern is avoidable. At Altadena ADU Builder, we structure every contract around the statutory deposit cap and milestone-based payments tied to completed, inspectable work — because a payment schedule built on dates instead of deliverables is a red flag, not a convenience. Before you sign with anyone, compare their proposed deposit against the $1,000/10% limit and walk away from anything larger.

California's Payment Rules: The $1,000 Deposit Cap and Milestone Law

Most ADU owners never read the fine print on payment schedules until money is already gone — and California's rules are surprisingly strict about what a contractor can ask for up front. Knowing them before you sign is the difference between a protected build and a $30,000 lesson.

The core protection is the $1,000-or-10% down payment cap in Business & Professions Code §7159. On home improvement contracts over $500, a contractor may collect only $1,000 or 10% of the contract price, whichever is less, before work begins. According to California contractor payment rules, contractors also may not request or accept payment exceeding the value of work performed or materials delivered — and materials count only once they reach your property.

Violating the deposit cap is not a technicality. It is a misdemeanor carrying a fine of $100 to $5,000, up to a year in county jail, plus CSLB discipline. An NBC Bay Area investigation found an ADU builder that collected a $19,500 deposit — 19 times the legal limit — and refunded it only after media pressure.

The prompt payment framework works in both directions:

• Owners must pay a proper progress payment demand within 30 days on private projects, and contractors must pass funds to subcontractors within 10 days of receipt.
• Wrongful withholding carries a 2% per month penalty plus attorney's fees, and owners may withhold no more than 150% of a good-faith disputed amount.
• These protections are non-waivable — any contract clause attempting to waive them is void as against public policy.

Two new laws take effect January 1, 2026. SB 440 creates mandatory change-order claim procedures, 2% monthly interest, and stop-work rights, while SB 61 caps retention at 5% instead of the 10% industry norm. Here is the part most ADU owners miss: both laws exempt residential projects that are not mixed-use and do not exceed four stories, so a typical single-family ADU stays under the older §7159 baseline rules. If a contractor cites SB 440 or SB 61 to justify an unusual payment demand on your backyard build, that is a red flag worth questioning.

At Altadena ADU Builder, we structure every ADU contract around these baseline rules — capped deposits, milestone payments tied to inspections, and final payment held until walkthrough and lien releases. Before signing anything, verify your builder's deposit against the $1,000/10% cap and confirm their license is active.

What a Legal ADU Payment Schedule Actually Looks Like

A legal payment schedule for a California ADU looks nothing like what most contractors hand homeowners. Instead of "half down to order materials" — described by one licensed contractor as the most common illegal request in California remodeling — the law requires a capped down payment, milestone-based progress payments, and lien releases at every step.

Start with the deposit. On home improvement contracts over $500, California caps the down payment at $1,000 or 10% of the contract price, whichever is less, per Business and Professions Code §7159. Violating the cap is a misdemeanor carrying fines of $100 to $5,000 and up to a year in county jail. As NBC Bay Area reported, one ADU builder collected a $19,500 deposit — 19 times the legal limit — and refunded it only after media pressure.

After the deposit, every progress payment must track the value of work actually performed or materials delivered to the property. The schedule should be tied to completed milestones and passed building inspections — never calendar dates. As one practitioner puts it, "'$10,000 every two weeks' is not a schedule of progress payments; it is a loan to the contractor."

A compliant structure looks like this:

• Down payment capped at $1,000 or 10%, whichever is less
• Progress payments released only after milestone completion and inspection sign-off
• Final payment held until final inspection, walkthrough, and punch list are complete
• Conditional lien releases collected before each payment; unconditional releases after funds clear
• All change orders written and signed before any extra work begins

Lien releases deserve special attention. California requires statutory-form releases — conditional releases (Civil Code §§8132, 8136) before payment and unconditional releases (§§8134, 8138) after — and non-statutory forms are unenforceable. This matters because unpaid subcontractors can lien your property; the NBC Bay Area investigation documented a subcontractor owed roughly $55,000 for foundation work on an ADU project.

The change-order rule exists for a reason. One documented garage conversion quoted at roughly $85,000 ballooned to about $130,000, driven by unpriced scope changes and verbal agreements. Written, itemized, signed change orders before any extra work begins are the homeowner's only real protection against that kind of creep.

At Altadena ADU Builder, we build every ADU contract around this milestone-and-inspection structure, because a payment schedule that follows the law protects both sides — and because a backyard ADU project should never become a cautionary tale.

Red Flags and Your Remedies When a Builder Breaks the Rules

A $19,500 deposit on an ADU contract — 19 times California's legal limit — is exactly the kind of violation that slips past homeowners who don't know their rights. Knowing what to look for, and what the law lets you do about it, is the difference between a smooth build and an expensive nightmare.

Start by verifying your contractor's license on the CSLB website before signing anything. In one documented abandonment case, a homeowner lost roughly $24,000 on a job that stalled at about 60% complete — under an expired plumbing license with no electrical permit pulled.

Watch for these red flags during bidding and contract negotiation:

• A deposit request above $1,000 or 10% of the contract price, whichever is less — the statutory cap on home improvement contracts over $500
• Cash-only pricing or "discounts for paying cash"
• Verbal change orders instead of written, signed amendments before extra work begins
• Refusal to sign conditional lien releases before each payment
• "Half down to order materials" — described by licensed contractors as the most common illegal request in California remodeling

A date-based schedule — "$10,000 every two weeks" — is not a progress payment plan; it's an unsecured loan to your builder. California law prohibits contractors from requesting payment that exceeds the value of work performed or materials actually delivered to your property.

If a builder breaks these rules, you have real enforcement paths. Deposit-cap violations are misdemeanors punishable by fines of $100 to $5,000 and up to a year in county jail, plus CSLB discipline — filing a state complaint is a documented enforcement route, as NBC Bay Area's investigation of ADU builders showed. On the payment side, an owner who wrongfully withholds progress payments owes a 2% per month penalty plus attorney's fees, and withholding on a good-faith dispute is capped at 150% of the disputed amount.

You also hold cancellation rights: three business days for contracts signed at your home, five days for homeowners 65 and older, and seven days for disaster repairs — with the contractor required to refund within 10 days.

This is the framework we build on at Altadena ADU Builder. Every backyard ADU and garage conversion project we run uses milestone-based payments tied to completed, inspectable work — never dates — with final payment held until final inspection, walkthrough, and signed lien releases. If you want to see what a compliant payment schedule looks like for your project, take our ADU planning quiz or request a cost estimate through our site.

The best protection is a contractor whose payment structure already follows the law.