so i am looking through trying to find decent r values in foam board insulation, and I can get an r10 and double it. I have called around to about 6 places for spray closed cell insulation and they are wanting to charge me 1200 for my 150 sq ft space. So, because my hubby can't regulate his temp we will stick to the coast quite a bit but definately want to be comfy, we may take off into the mountains in the fall but never winter.
What I am asking
What R value rating should I get for the bus to keep it cool enough.