See an example plan
Here is what the planner returned for a one-bedroom detached ADU in San Diego, built as a rental. Yours is based on your own answers.
Cost
A cost range for your area, not a national average. Construction, design and engineering, permits and fees, and contingency are shown separately, and site conditions like a slope, septic, or a utility upgrade are priced in.
Financing
A home equity loan or line, a cash-out refinance, and a construction loan compared against your budget, with the cash you need upfront, the estimated monthly payment, and what to watch for with each. If you plan to rent the unit, you see how rent offsets the payment.
Local rules
Whether your state requires cities to allow ADUs, the limits on size, setbacks, parking, and fees, and who to call at your permitting office. Every rule links to its official source and shows when we last checked it.
Next steps
Your plan ends with a plain-language project brief and the questions you still need answered. Send it to any contractor you talk to, or ask us to introduce you to one who builds this type of ADU in your area.
How it works
Your ZIP code sets local building costs and the state rules that apply.
Who it’s for, the type and size, and anything unusual about the lot. Not sure yet? The planner compares the options.
Cost, financing, local rules, and a builder-ready brief. Nothing goes to a contractor unless you ask.
An accessory dwelling unit is a second, smaller home on the same lot as a house. It can be a detached backyard cottage, an addition attached to the house, a converted garage, or a converted basement, attic, or unused wing.
It depends mostly on the type of unit, its size, local construction rates, and your site. Converting space you already have usually costs the least, and a new detached unit usually costs the most. The planner gives you a range for your ZIP code with construction, design and engineering, permits and fees, and contingency shown separately.
Some states require cities to allow ADUs; in others, the city or township decides. The planner shows the state rules for your address with their official sources, plus the property-specific questions to confirm with your local permitting office.
The most common paths are paying cash, a home equity loan or line of credit, a cash-out refinance, or a construction loan. The planner compares them for your budget, including the cash needed upfront and the monthly payment for each.
Yes, it’s free. Nothing is sent to a contractor while you explore your plan. If you decide you want help, you can ask us to introduce you to a contractor, and only then do we receive your project brief and contact details.