This isn't new.
In MA FFLs attached to dwellings are generally not allowed. I always thought this was a state thing (like a CMR or something) but I forget offhand. All I know is that new licensees will not get a license approved if their business touches their house. This also assumes that all the other ducks have been gunned down- eg, local zoning and other considerations.
The ATF will look for ANYTHING to deny you- and I mean anything. They frequently deny licenses for compliance failures on nearly meaningless local laws and ordinances. Say for example, your town had an ordinance that said you have to have a permit to have a toilet, and your dealership has a toilet in it without a permit- they would use that as a reason to deny your FFL application. You have to have all your crap together, twice over, in MA, to maintain an 01. If you are really serious about this you should do more research or obtain a gun lawyer.
-Mike