Ours is deep in an insulated tandem garage. In the garage it does not seem to ever get below 32 degrees during our Wisconsin winters of late.
If I had no garage I think I would build a carport to keep the sun and rain off. I would worry mostly about
solar degradation.
My previous
Scamp was stored outside for 15 years and it showed, though still it did not leak much.
Windows needed some sealing attention when I bought it at 11 years of age and that kept it nice and dry.