We are leaving our trailer at the camp site all winter in northern Wisconsin. The campground host says most yearly campers leave trailers uncovered and don't have any problems. A friend at home always uses a tarp and prefers that. Some say cover for birds, weather, etc. Others say they have problems with mold, wear areas, etc when covering. If camper sits out during the other 8 months, will a little snow hurt it? What is the experience out there? Thanks!