ADU Cost Calculator, Process Guide & Vetted Builders

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The 2026 ADU Homeowner's Playbook, free.

A 27-page PDF covering process, costs, permits, and financing — plus monthly updates on what's changing in state ADU law.

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Independent guidance for U.S. homeowners building Accessory Dwelling Units.

The ADU process

Overview
Planning
Design
Permits
Financing
Construction
Inspection & occupancy

Tools & calculators

Cost calculator
ROI calculator
Loan calculator
Feasibility check

Plan & compare

ADU cost
ADU types
Floor plans
Financing options
Permits by city
Compare ADUs

Find builders & homes

Builder directory
Homes with ADU
Buying guide
For builders

Company

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