I use a cover because I ain't got no covered storage either. My RV has always been covered from what the PO told me and all the stickers look new. BTW, mine is a 1992. So after comparing it to others that were much newer but in worse shape, I spent the money to buy a new cover (my old one ripped in a strong wind storm). Now I work a little extra to get the straps tight under the RV where before I didn't...live and learn. It's not easy getting up on the roof with the cover, but it's better than the damage the sun will do to it....but that's just one man's opinion.
Tom