neighbor does spray foam. The type he uses gives an r18 rating on the walls, r28 for the roof, fire and water proof. Goes on 6 inches thick for the walls, 10 inches for the roof.
3800 a piece? Currently they’re 4100 plus delivery for us here. A year ago when I got quote, they were 1400 plus delivery. But bare in mind, the further away from a port you are, the more expensive they are. If I could haul them, or find someone too, I can get them from up by Chicago for 1/3 of the price.