I don't have any first hand experience but I do know that when we drive Alt. 19 from Dunedin to Palm Harbor there are several businesses on that stretch that have signs advertising RV storage. I called and got prices from them a while back. Most were uncovered but you had access to electric. I think it was the UHaul place in Oldsmar I called and was told they offered covered storage. They were helpful but it was a lot more than we want to to spend each month. We were lucky enough to squeeze ours in the back yard when we finally tried.
The Evans' Family
WBCCI 7091, Unit 153 & AIR 88474
1977 Overlander / 27' ~ The Attitude Adjuster
1997 Airstream Excella / 34' ~ The Sane Asylum