If they advertise a storage less than you need why would you go get it....most companies exaggerate things. Best bet would be to have the current owner measure the space.
Delam could be fine, I would be concerned what other water damage there is that is not visible.
03' Fleetwood Southwind 32VS
Enclosed Trailer hauling the toys
05 525 EXC KTM
15' FE350s Husqvarna/KTM
07 Rhino, long travel, 4 seater