Land acquisition, permitting, grading, hardscaping, wells/plumbing/septic, electricity, shared recreational amenities . ..

There's some complicated ways around it and things may have improved, but I can tell you that I was personally threatened with being charged with a felony in 2019 for renting my property even though I had gone through the proper permitting.

But, it does appear that all of the current uses are permitted.

. - Feasibility & Permit-ability: If you know where to look you can still secure a STR permit in most cities or counties from Brookings to Astoria.

We have so far removed all the stuff, gutted almost the entire house, and are currently stuck in permit jail working on the septic relocation.

We wouldn't have any plans to rent the garage conversion out long term, it's just mostly extra space for us.Or (in theory, if zoning/permits line up) can I convert the garage to a guest suite without the separate address/utilities?

If such is the case, I'd walk away and continue the hunt elsewhere.If they will allow access, you may find that renovation was started but no permits were pulled and no inspections passed.

If so you may want to do it with permits, so that it shows on tax records.

If this is the case, you're going to be walking a very fine line between what you're legally allowed to do as an unlicensed entity, even if a GC does agree to put their name on the permits. 

I start herehttps://www.huduser.gov/portal/ushmc/chma_archive.htmlFind your city and state and get a quick picture of how the city/metro is doing (population, demand and current approved permits for new construction.