Taking the toy hauler up to the ski resort? Any problems?

IF I was going into a known sub-freezing environment I'd definitely take some precautions, like a heater in the under belly, heat tape on the drain line and plastic film inside the windows for rudimentary storm windows, single pane glass will lose a LOT of heat and you'll feel the draft as the cold air falls across the windows. Most trailers have windows right behind the seating so you're sitting very close to major heat loss source.