How to compare ADU builders before you sign

Start with the state. Every contractor building an ADU in California needs a current CSLB license, and every Vera Home listing shows whether that license checks out against the state's own records. A builder who can't show you a live license number is not a builder you compare; they're one you cross off.

Then ask to see a job in progress. Not a finished photo, a site with people on it. You're looking for three things: whether the crew acts professionally (on time, sober, courteous to the homeowner), whether you can spot obvious safety hazards (open trenches without barriers, ladders on uneven ground, cords through puddles), and whether the workmanship meets your standards up close. Rough framing tells you more than a glossy kitchen photo ever will.

If a site visit isn't possible, grade them on three things you can still see. Communication: how fast and how clearly they answer, and whether they answer the question you asked. Contract detail: the exclusions list matters more than the inclusions list, and allowances for cabinets, tile, and fixtures should be spelled out with what happens if you choose above them. Past work: ask for two addresses from the last year and drive by.

Know what too cheap looks like. Build this site's free ADU budget for your build type first, then treat any bid far below the bottom of that range as a question, not a bargain. Low bids usually mean something is missing: permits, utility tie-ins, the panel upgrade, the solar panels a detached new build requires, or the landscaping that gets torn up for trenching. The change orders arrive later, when you can't walk away.

Last, compare like with like. Two bids only tell you something if they price the same scope, so hand every builder the same budget brief and the same plans, and ask each one to list what's excluded. The builder whose exclusions list is longest and most specific is usually the one who has done this before.