Yeah, about the "posh." I thought so, until I saw them sitting on the porch and thought, "That's a metal building, not a ranch house."
They're sometimes called pole barns, and this one looked to be intended as a residence, rather than converted from something else. But you're right--such buildings used to be used as storage facilities or garages.
Interestingly, manufactured houses are also metal buildings intended to be a residence, but looked down upon (e.g., a "double-wide"). I guess their problem is that they're just not big enough, or painted red.
It's not a Mc word, but