385 sqft assembly cost for studio home?

[Aloha Estates]

If I purchase an Argus studio (385sqft) for $12K, what am I looking at for a contractor to build just the shell=roof,walls,pier & post,subfloor and windows? I think the $100-$130sqft.cost should be lower since the home is already purchased. All contractor has to do is build. I know that cost money also. Also, what is the going rate for a solar package kit to run such a small home?

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