Archives

We modeled a typical 2-car garage conversion ADU in Los Angeles County (~450 sq ft living). Total: $190,000. See which phases shrink vs a new detached build — and which grow.

Soft costs on California ADUs typically land around $28,000–$40,000 before construction starts. Here is every design, engineering, plan check, and fee line — with ranges by jurisdiction type.

Take the $320,000 construction model (and ~$381,000 all-in year-one) against realistic LA County ADU rents. Simple payback, cash-on-cash, and what breaks the model — with a hard not-financial-advice disclaimer.

Same 800 sq ft ADU plan priced two ways: LA coastal band near $380,000 ($475/sq ft) vs Inland Empire near $300,000 ($375/sq ft). Six phases, same drawings — labor, fees, coastal review, and access drive the swing.

The $320,000 and $215,000 construction models are not what you actually spend. Add 12% contingency, construction loan interest, Prop 13 ADU-only tax, vacancy, and optional management — here are clear year-one all-in tables.

Same 800 sq ft detached ADU, two delivery methods. Site-built baseline $320,000. Modular lands near $288,000 after crane and transport — here is where each phase saves or grows.

We modeled a 400 sq ft detached ADU in Los Angeles County. Total: $215,000 — or $537 per square foot. Here is every phase, why fixed costs dominate, and when 400 still makes sense.

We modeled an 800 sq ft detached ADU in Los Angeles County and priced every phase. Total: $320,000. Here is where each dollar goes and why smaller is not cheaper.