How to choose an ADU (accessory dwelling unit) builder: 10 questions to ask first

The total at the bottom of a proposal only covers what the proposal lists. A finished ADU also needs a zoning check, answers to permit comments, a utility trench, a foundation, and a delivery day. It also needs someone to pick up the phone when the inspector wants a change.

Ask these ten questions before you sign with anyone, including us.

1. How many ADUs have you actually finished?

A builder who has done one or two ADUs works differently from one who finishes them every week. Ask for a count. Then ask to see jobs that look like yours. That might be a tight backyard, a slope, a septic system, or a city lot with a power pole in the way.

Wolf has delivered homes from the Battle Ground factory across a lot of jurisdictions in Washington, Oregon, and beyond. A portfolio doesn’t mean your lot will work. It does mean the crew has probably seen your lot’s problems before.

Browse case studies and the photo gallery before you compare bids.

2. Will you look at the property before I commit?

Pick a floor plan after someone has looked at the property. The questions that matter most are the practical ones:

• What does this zone allow, and who reviews it: the city or the county?
• Where can the home sit once setbacks, easements, and the existing house are drawn in? (A setback is the distance a building has to sit from the property line.)
• How do water, sewer or septic, and power reach that pad?
• Can a truck, or a crane, actually get there?
• What has to be dug, cleared, or torn down first?

A free property evaluation is where we start. It’s a first look at zoning, setbacks, and what’s generally allowed on the lot. Utilities, access, and site prep get worked out as the project moves forward. Be wary of a builder who wants a deposit before they’ll talk about your lot.

3. Who handles the permits?

A building permit takes more than one form. Depending on the jurisdiction, it can mean a site plan, engineering, stormwater notes, a utility letter, a review cycle, a comment letter, and a resubmittal.

Ask in plain language:

• Who draws and submits the packet?
• Who talks to the reviewer?
• Who answers when they want a change?
• Which pieces are still yours?

At Wolf, our permit team files the permit and handles the comments, and we schedule permitting alongside production. See how permitting works on a Wolf job. The jurisdiction still sets its own review times.

4. What is actually in the quote?

Two proposals can show similar totals and cover different work. The lower one often left out the costly parts: engineering, excavation, the utility trench, delivery, the set, or the deck the drawing seemed to include.

Ask for a written breakdown. A complete ADU quote has a line, or a clear exclusion, for each of these:

• The home itself, with the selections that change the price
• Permitting, including the comment cycle
• Engineering, and a survey if the lot lines aren’t already known
• Excavation and the foundation
• Utility connections: water, sewer or septic, and power
• Delivery and the set
• Decks, porches, and other exterior work the drawing shows
• Site prep: grade, trees, demolition, drainage
• Finish work and the inspections through occupancy

Wolf’s proposal lists permits, selections, delivery, utilities, grade, trees, and demolition as separate lines. That way you can see your total project cost. The cost page has our published price ranges, and your lot still gets its own number. If a bidder’s total is lower, mark which of those lines are missing before you decide it really costs less.

5. Who coordinates the whole job?

It’s easy to hire a factory for the house, an excavator for the hole, an electrician for the trench, and another company for the foundation. Then you find out nobody is running the schedule. That usually leaves it to you.

Ask who schedules the site and who checks that the pad is ready before the home leaves Battle Ground. Ask who’s on the hook if those dates slip. On a Washington or Oregon turn-key job, that coordinator is Wolf, from the evaluation through delivery and setup. Surprises still happen, but you have one company to call about them instead of three. Outside those two states, Wolf delivers and sets the home, and local contractors handle the site work and utility connections. So confirm who runs that schedule before you sign.

6. How is the home built?

With a site-built ADU, framing, roofing, plumbing and wiring, and finishes happen in your yard, in whatever weather that month brings. A Wolf home is built indoors in Battle Ground and inspected along the way. Then it’s hauled to a pad that was prepared while the house was in the shop.

You still get dirt work, a foundation, and a set day, the day the home is placed on its foundation. What you skip is six months of construction behind the house. If keeping the yard usable matters, ask every bidder how many weeks of full construction will happen on the property. The factory tour notes show what that indoor work looks like.

7. How does the home get onto the lot?

People tend to ask this one too late. Driveways, overhead lines, fences, trees, slopes, and the neighbor’s garage decide whether a module (one factory-built section of the home) can reach the pad. A good builder brings that up early.

We’ve set homes on urban infill lots, rural acreage, and hillsides. A home that fits on the survey can still be hard to get into the yard. If you’re unsure, start with a free property evaluation, which looks at zoning and setbacks first. Access gets a closer look as the project moves forward, before you’re locked into a plan.

8. What happens after the house is built?

Once the module is built, someone still has to deliver it, set it, connect utilities, finish the exterior, and walk the inspections.

Ask where each builder’s job ends. Wolf handles delivery and set on every home it builds. That’s true in Washington and Oregon and on the longer hauls to other western states. In Washington and Oregon, the connections and the punch list that follows (the final round of small fixes) are part of the same job. The setup checklist walks through each step.

9. Can I see finished work and talk to owners?

Photos are a start, but finished houses and owners who’ll talk to you tell you more. Look for jobs similar to yours, and look for a pattern. Did people know who to call? Did the project actually finish? Did surprises get explained before they turned into invoices?

Testimonials and case studies are a start. Ask any builder, us included, how long they’ve been doing this under the same company. Wolf holds Washington L&I license WOLFIII921BD and Oregon CCB 184044, and you can look both up yourself. A license is the minimum requirement.

10. What happens when the lot doesn’t match the drawing?

Something will be different. The sewer is farther than the sketch showed, the reviewer wants a different foundation detail, or a tree has to come out. Ask who tells you about a change, who prices it, and who decides.

A company that has done this many times still runs into surprises. It’s just less likely to be seeing a normal site problem for the first time on your job.

Compare the scope

Say one bid leaves permitting, site work, or project management on your side of the line. Then the lower total can end up costing you more. Put the proposals side by side and mark whose name is on each task.

ADU builder vs. general contractor goes through the same questions for that choice. Either kind of builder can work if the scope is clear in writing.

If you’re building in Washington, Oregon, or beyond

We offer turn-key service (evaluation, permitting, site work, delivery, and setup) in Washington and Oregon, from our factory in Battle Ground. Outside those two states, we deliver and set the home. Local contractors handle the site work and utility connections, and we quote each project on its own. If a lot won’t work, we’ll tell you as soon as we know, before you’ve paid for drawings.

If you want the model lineup after the lot checks out, start at ADU builder and the plans. If you only have an address, send it to us. The evaluation is free and doesn’t require a contract.