Here in Texas, a good hailstorm has a good chance of totaling a RV, especially if it goes undetected and the subsequent water intrusion causes rot.
My #1 recommendation: Maintain the roof. Grab those tubes of Dicor and every year, go inspect and reseal. If it even looks loose or cracked, scrape the old off, sputter on new, call it done. Or go with Eternabond.
Even neglect for months can make an impact on a rig. I'd recommend at least looking it over and running the A/C monthly if weather permits. For motorhomes and such, run the generator as well.