Richmond, Contra Costa County

ADU / Guest House Cost in Richmond, CA

Richmond remodeling costs are nearthe California state average. Here's what a typical adu / guest house costs in Richmond in 2026, based on a 500 sqf project.

Budget
$131,250
$263/sqf
Mid-Range
$210,000
$420/sqf
High-End
$315,000
$630/sqf

Cost breakdown

Foundation & Framing
25%$52,500
Mechanical (HVAC, Plumbing, Electrical)
20%$42,000
Interior Finishes
20%$42,000
Exterior & Roofing
15%$31,500
Kitchen & Bath Fixtures
10%$21,000
Permits, Plans & Engineering
10%$21,000

Breakdown based on mid-range estimate of $210,000

Typical Timeline
4-8 months
Permits Required

Building, electrical, plumbing, mechanical. May require plan check.

Remodeling in Richmond

West Contra Costa city experiencing a renovation renaissance. Older homes in the Point Richmond and Annex neighborhoods are being restored. Marina Bay area attracts higher-end renovations.

California allows ADUs on most residential lots since 2020. An ADU adds living space and rental income. Cities must approve or deny within 60 days of a complete application.

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Other projects in Richmond

Kitchen Remodel
$31,500 – $94,500
Bathroom Remodel
$15,750 – $50,400
Room Addition
$63,000 – $173,250
Roof Replacement
$13,125 – $39,375
Exterior Paint
$5,250 – $18,375
Whole House Remodel
$283,500 – $945,000

ADU / Guest House cost in other California cities

Roseville
$118,750 – $285,000 | Placer County
Orinda
$156,250 – $375,000 | Contra Costa County
Fremont
$143,750 – $345,000 | Alameda County
Huntington Beach
$137,500 – $330,000 | Orange County
Encino
$137,500 – $330,000 | Los Angeles County
Anaheim
$131,250 – $315,000 | Orange County
Glendale
$131,250 – $315,000 | Los Angeles County
Redondo Beach
$137,500 – $330,000 | Los Angeles County

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