How to Choose an ADU Contractor in Los Angeles
Choosing an ADU contractor is the decision that determines whether your project comes in near budget or $80,000 over it. Almost everything that goes wrong on a Los Angeles ADU was visible in the license record, the bid, or the contract before anyone signed. This guide is the full checklist we use on behalf of families — free, in detail, whether or not you ever call us.
Six checks before you take a single bid seriously
Verify the license yourself — don't take the number on the truck
Look the contractor up on the California State License Board site by license number, not by name. Confirm the classification is B (General Building) for a new-build ADU, the status is active, there are no outstanding disciplinary actions, and the bond is current. Check the personnel listed on the license actually match the people you've been meeting.
Demand current certificates of insurance, sent by the insurer
General liability of at least $1 million and workers' compensation covering every person who will be on your property. Ask the insurance agent to email the certificate directly with your name as certificate holder. A PDF forwarded by the contractor proves nothing about whether the policy is still in force this month.
Call three references who did your project, not any project
A kitchen remodel reference tells you little about a family's experience with a detached ADU, a service upgrade, and an eight-month schedule. Ask each reference: did the final price match the contract? How many change orders? How were problems handled? And the one that gets honest answers — would you hire them again for something bigger?
Visit an active job site
Fifteen minutes on a working site tells you more than any brochure. Is it clean and organized? Are materials protected from weather? Is a supervisor present? Do the trades know what's happening tomorrow? Sites reflect management, and management is what you're actually buying.
Confirm who is really building it
Many ADU companies are sales and design shops that subcontract the whole build. That isn't automatically bad, but you need to know who holds the license doing the work, who supervises daily, and who you call at 7am when something is wrong.
Ask about their plan-check record with your specific agency
A contractor who has cleared LADBS or LA County Public Works plan check repeatedly on ADUs like yours will save you months. Ask how many correction rounds their last three ADU submittals took.
Nine red flags in bids and contracts
None of these mean a contractor is dishonest. All of them mean you should slow down and get an answer in writing before signing.
A deposit over 10% or $1,000
California law caps a residential down payment at 10% of the contract price or $1,000, whichever is less. A contractor asking for 30–50% up front is either unaware of the law or planning to use your money to finish someone else's job.
Lump-sum pricing with no line items
'Construction — $312,000' is a number, not a bid. Without line items you cannot compare builders, cannot verify a change order, and cannot tell what was quietly excluded.
Allowances set unrealistically low
A $9,000 allowance covering all cabinets, counters, and appliances is a device for making a bid look competitive. You will pay the real number later, at the contractor's markup, when you have no leverage.
An exclusions page you're told not to worry about
The exclusions page is the most important page in the document. Permits, utility upgrades, site drainage, landscaping restoration, and debris haul-off all hide there.
Uncapped change-order markup
If overhead and profit on change orders is unstated or open-ended, your fixed-price contract is fixed only until the first change.
Front-loaded payment schedule
Payments should track completed, inspected work. If 85% is paid before drywall, nothing motivates a fast finish on the last 15%.
No written schedule with milestones
'About eight months' is not a schedule. You want substantial-completion dates and a stated remedy if they slip.
Pressure to sign this week
Discount-expires-Friday urgency on a six-figure family decision is a sales tactic, not a business reality. Every legitimate builder will hold a price for a reasonable review period.
Reluctance to put a verbal promise in writing
If it isn't in the contract, it doesn't exist. A builder who says 'don't worry, we always do that' and won't write it down is telling you exactly how the dispute will go.
Ten questions that reveal who to trust
Ask all ten of every builder, and write down the answers. The pattern across three contractors tells you more than any single answer does.
- How many detached ADUs have you completed in Los Angeles in the last two years, and can I see two of them?
- Who supervises my project daily, and how many other jobs will they be running at the same time?
- What's your average number of plan-check correction rounds with this agency?
- What does your contract say about liquidated damages or remedies if the schedule slips by 60 days?
- How do you price change orders — fixed markup, cost-plus, or negotiated each time?
- What is specifically excluded from this bid?
- Do you carry workers' comp for every trade on site, including subs?
- What's your warranty, what does it exclude, and who honors it if the company is sold?
- Will you accept a payment schedule tied to inspected milestones?
- Can my advocate review the contract before I sign, and are you comfortable with that?
Why the lowest bid usually costs the most
A bid that comes in $70,000 under the others is not generosity and is rarely efficiency. It's one of three things: missing scope, artificially low allowances, or a company that needs cash flow badly enough to buy the job and make it back on change orders.
The third one is the dangerous version. A builder who bid below cost has to recover it somewhere, and the recovery mechanism is always the same — every ambiguity in the drawings becomes a change order, and every change order arrives after demolition, when walking away costs you more than paying does.
The fix isn't to pick the highest bid. It's to normalize all three to identical scope before comparing. Our Los Angeles ADU cost guide walks through how to compare bids apples-to-apples, and the permit guide explains which soft costs belong in the bid at all.
You never face a contractor alone
Everything above is work. It's phone calls to the license board, insurance agents, references, and three builders who each want a decision this week — while you're also managing a parent's care and your own job.
That's the entire reason Multi-Gen Homes exists. We do these checks before you ever meet a builder, sit with you through bid comparison, and read the contract line by line beside you. See how the four-step advocacy process works — it costs your family nothing.
Contractor vetting FAQs
The questions worth answering before you sign a six-figure construction contract.
"I'm paid only after you're delighted. A vetted contractor pays my fee once your family is satisfied with the plan and the price — never you. That's the whole reason I can tell you the truth about a bid, even when the truth is 'walk away.'"
— Danniel Fuchs, Founder & Family Advocate, Multi-Gen Homes
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