The top of the fridge unit has a drop in sink and stove that I am planning on installing this fall. This allows inside cooking and washing whil standing up with plenary of room. I’ll also add a roof vent van for exhaust of increased moisture from heat and cooling.
I actually built this with the intent of overnights at Mt Baker to snowboard. I haven’t installed the propex heater yet, but it would be like a mini home forced air heat system. I have camped on cold alpine spring nights in pouring rain. We used the inside space most of the day for a few days straight.