I just use a cover. Mine is made by Classic Industries, and it held up under 2ft of snow last winter. Depending on the size of your RV, they can be $400~800.
When we stored a previous boat at home, I had one of those $200 canopies, but it was not snow rated and each time it snowed, I had to remove it. What a pain that was. The cover we have now is just not any need to do anything like that.
The only thing that works on a RV is the owner...