There is no such thing as a 4 season trailer. Extended perhaps but down to 20 degrees and less, no way. I have read about people pulling their trailers up to the ski hills. If you read close enough, they talk about draining the lines, carrying water in jugs and using the facilities at the hill. I have been down to the high 20s in mine and needed to keep the heat running not to freeze up. Don't recommend this.
My cousin has an Arctic Fox. Probably the most solidly built trailer I have seen. It is heavy and expensive but very well made in my opinion.
