I left my old 5th wheel at the campground near Myrtle Beach (Willowtree) over the winter. We had planned on one more trip south but I took sick and we couldn't go. It was never winterized but we got off lucky with no plumbing issues.
The next season we went stayed awhile I started to tow it home. Less than 1/2 an hour on the road the front drivers side gelcoat blew completely off all the way back to the window. We had a small leak and water got in behind. It had also gone through two small hurricanes / tropical storms while stored. Lots and lots of rain.
I said right there and then I would never store it that far away again. The farthest my new one from me is when I store it an hour and a 1/2 away in an underground mine over the winter.
The storage facility at Willowtree was first rate and very secure. It was nice to drive all the way there and just hook up and enjoy but I just don't feel good about having it that far away especially with the new one.
I don't know if you are paying to store it now but maybe find a place a little closer to home as a compromise. During the camping season mine is only 10 minutes away at a very nice storage yard.
Dave