Free tools · Updated 2026

What does an ADU actually cost to build?

Real construction costs, permit fees, and zoning rules for accessory dwelling units — itemized by city, calculated for your project.

Itemized estimate by state, type, size, and finish level.

Living space or full ADU — itemized by scope and garage size.

Coming soon — break-even timeline if you rent your ADU.

Guides

Plan smarter

Cost, timeline, rental value, and the 750 sq ft fee rule — an honest comparison of the two main ADU paths.

The real financing options for a six-figure ADU project — home equity, cash-out refis, renovation loans, and the grant programs worth checking.

From feasibility to certificate of occupancy: what actually happens at each permitting stage, how long it takes, and where the money goes.

Rental yields, property value, the costs spreadsheets forget, and when an ADU genuinely pays — without the industry gloss.

City guides