Here‘s some prefab budget builder:

5 modules, 2591 sf
San Francisco Bay Area, Flat Site

Factory Construction $ 345,000
Site Improvements (incl. site prep, demo
existing structure, foundation, button-up)
$ 380,000
Transportation + Setting $ 72,000
Professional Services $ 42,000
Other Soft Costs $ 66,000
Preliminary Cost
$ 915,000
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