Yes, my friends, this is how it's done. Just spray the whole rig with spray-on insulation, put a couple candles in there and your worries are over. Me thinks it would be easy to cool too when the hot summer days come.
I took this photo in one of our oilfield trailer courts last year. I can only imagine the tenants may have spent a mighty cold winter in this thing and decided they weren't doing that again. I really have no idea. I just thought it would fit in as a winterizing thread. I'm thinking the cost of insulating was higher than what the camper was worth.