I would check out the storage yard very carefully. They tend to be located in out of the way places, often near less than desirable neighborhoods and frequently not that secure. A pass card, special keys and pins do not keep out the bad guys, and the larger storage areas with many units just create more traffic and allow more opportunities for the undesirables to sneak in.
Rather than a large secure facility I might consider local campgrounds that have storage available. It may not be the razor wire and halogen lights sort of place, but rather people around who have an interest in RV's.
Paul and Janet Braun
2003 Toyota 4Runner V8 now 2012 Toyota Sequoia V8
Escape 19' 2010 now 2014 Escape 21'