Per-city prefab and modular build costs, permit and development impact fees, SB 9 lot-split rules, and utility connection charges — researched city by city for homeowners and small investors building on Bay Area lots.
Alameda County
Contra Costa County
Santa Clara County
San Mateo County
Each city page covers what a prefab or modular home actually costs to put on a lot there — factory price plus site work — alongside the city's building permit and plan-check fees, development impact fees, SB 9 urban-lot-split status, utility connection charges, and how prefab compares with stick-built locally. Every figure traces to city fee schedules and public records — see our editorial policy.