First, the idea of both a group land buy and a group town buy have been floated:
Day Dreaming: Incorporating a NES Town
The idea of a group buy on land has been floated before. How about Iceland?
Second, if the group was legitimately serious (like say if the case against Maura Healey went seriously south or if some atrocious bills got passed and things were simply not tenable for gun owners in Mass/CT/RI, etc.), we could probably buy a town like the colonial settlers did from natives.
Unorganized Townships | ME-Somerset County, Maine | Official Website
Large parts of Maine are still undeveloped townships. To get a functioning settlement going with a full economy, you need waves of settlers (and funding and supplies). The Winthrop Fleet was about 700-1000 Puritans and they needed re-supply in a year. Obviously we wouldn't be starving, but a project like this would need continual funding and some form of potential income to tap into and "export", like the settlers did with agricultural products, furs, and eventually manufactured goods. NES craft breweries and distilleries?
A large degree of planning would be necessary to build a community properly, rather than a bunch of people living in some strange "commune" or "compound." Expect ATF raids if you call it a compound. Large amounts of people with blue collar knowledge and some professionals (doctors, lawyers, accountants, merchants [stores, gas stations, commercial endeavors, etc.]) would be necessary. The most important thing, however, is families.