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How to find a good ADU contractor

By the HyreADU research desk. Last checked .

The short answer

How to find a good ADU contractor comes down to five checks, done in order: an active license in the right class, ADU permits in their name in your city, insurance you can confirm, an itemized bid on the same drawings as the others, and payments tied to finished work.

1. License class and status

Look up the license on the CSLB site. In California you want a B General Building license, active today, in the exact name that will sign your contract. The CSLB’s ADU fact sheet names the B class for a full ADU build.

2. ADU work on the public record

Ask for addresses of finished ADUs and check them against your city’s permit records. Our permit contractor index lists firms named on ADU permits at two or more addresses in five California jurisdictions. Experience in your city matters because plan check habits and utility rules are local.

3. Insurance you can confirm

Ask for certificates of liability and workers’ compensation coverage, issued to you, and call the insurer to confirm them. A logo on a website proves nothing.

4. An itemized bid on the same drawings

Bids only compare when they price the same set of drawings. Ask each builder to list design, permits and fees, site work, utilities and the building as separate lines, and to name every allowance. Then lay them side by side in the ADU bid comparison.

5. A payment schedule tied to work

California caps the down payment on a home improvement contract at $1,000 or 10 percent, whichever is less (Bus. & Prof. Code § 7159). After that, each payment should follow a stage that is finished and inspected, not a date on the calendar.

What to do next: read the questions to ask an ADU builder, check what decides ADU cost, then tell us about your project. Matching is not live yet, so we reply with information, not a quote.

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Questions

How many bids should I get?

Enough to compare on the same drawings. Three is common advice. The number matters less than the fact that every bidder prices the same scope.

Should I pick the lowest bid?

Not by default. A low total often means a line was left out or carried as a small allowance. Compare line by line before you compare totals.

Are online reviews enough?

No. Reviews are hard to verify. A license record and permits in the firm’s name are public facts you can check.

Does HyreADU vet builders for me?

Not yet. Matching is not live. Our vetting standard sets out what we will check when it is.

Sources

HyreADU is a publisher. It does not design, permit or build ADUs, has no partner builders, and gives no legal, tax or engineering advice. Rules vary by state and city; California rules are labeled as such.