I know many beach towns would allow them as summer homes (forbidding permanent residence). otherwise you're looking at getting variances for most towns in eastern MA or buying land in VT :)

How many Sq Ft is the roof? if under 140 it'd be easy to install in a backyard in my town as a shed, so he could maybe post a "wanted: small corner of your property to rent" ad on Craigslist. might require some minor ignoring of the law, but with little repercussions other than having to move it if caught