ADU site conditions that can change a quote

What can you bring to the first visit?

Bring the property address, a simple description of the ADU you want and any existing plans or permit documents. Photos of the likely building area, existing garage and route from the street can help the first conversation. Do not enter unsafe spaces or investigate equipment to prepare.

Mention things you have observed: water collecting after rain, a structure you want removed, a narrow gate, a retaining wall or an old utility problem. Keep observations separate from conclusions. “Water collects here” is useful; “the drainage is adequate” is a professional conclusion you may not be able to make.

If you do not have records, ask the team which ones are worth obtaining first. Find the correct local agency rather than collecting forms for a different jurisdiction.

A conversion depends on what can actually be reused

A garage that looks substantial may still need work to serve as living space. Ask what the quote assumes will be kept and what the team needs to investigate about the foundation, structure, floor and existing services.

Do not treat the outside dimensions of a garage as a complete description of a conversion. Have the Contractor identify the scope of investigation included in the proposal and how findings will affect the design or price. Unknown existing conditions deserve a stated process, not a promise that nothing unexpected can happen.

When a specialist is needed

Ask the Contractor or designer what question needs answering and who is qualified to answer it. A surveyor, geotechnical or structural professional may be needed for a particular issue. The homeowner’s role is to understand why that work is needed and how the result affects the project.

Make removal and restoration visible

List the structures and features you expect to remove or keep: a shed, paving, a patio cover, landscaping or an old garage. Ask what demolition, disposal and restoration are included. If existing materials need special assessment or handling, have the team explain the next step before work begins.

Think about what the property should look like after construction too. A bid that restores a disturbed walkway is different from one that leaves outside work to you. Photos and a short marked plan can make these expectations easier to agree.

Flat ground and easy access are assumptions, not defaults

Ask the team to explain how the actual site changes the work. A slope may affect the proposed foundation or drainage solution. Limited access can affect how materials reach the building area. A retaining wall or nearby structure may need its own review.

You do not have to choose the construction method. Ask whether the proposal assumes ordinary access and whether the Contractor has visited the property. If machinery cannot use the assumed route, find out whether the quote already accounts for the alternative.

Locate the utility assumptions in the price

Ask how the ADU is expected to receive power, water and wastewater service. Bring account or provider information you already have. Separate the existing-service question from a preference for separate billing or meters.

Have unresolved upgrade or connection questions written down. If a proposal assumes a usable sewer connection and the property has septic, the quote is not ready for a meaningful comparison. Read ADU utility and meter questions.

What should you get out of the review?

Ask for a short description of the findings, the assumptions that remain and the next investigation, if any. You should be able to explain what the proposed price covers without repeating every technical detail.

Send the same new information to the other bidders if you are comparing proposals. Otherwise one company may price a confirmed condition while another still prices a simpler assumption. Keep a dated copy with the quote basis. Use the ADU quote-basis Step.

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