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Plant Prefab and Alchemy Architects Launch Net Zero–Ready Prefabs Starting at $170K

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The first Plant Prefab–built modular lightHouse ADU was completed earlier this spring in Sebastopol, California. This 423-square-foot lightHouse was completed for around $285,000. That figure breaks down to approximate costs of $210,000 for design, engineering and production; $60,000 for infrastructure and site work; and $15,000 for shipping and installation.