I had a nice one single-wide a couple of weeks ago. It is on a poured slab crawlspace. Tie-downs, lots of piers, drywall everywhere, and a real peaked roof with shingles. Heat pump, well insulated, built in 1990. Good for a lifetime or more. Oh yeah, it also has a plywood belly pan. BTW, if the tongue in the crawlspace is not allowed, how would they deal with the old ones that have the tongue integral to the frame? That's a holder for the planter full of tulips. []