...if you mean just dropping the truck camper onto its jacks at a storage facility (without truck under it), try a boat storage facility, like Lake Mead Boat Storage. I think they have inside storage, too.
Though not in Las Vegas, we have been storing our truck camper on jacks only and at other seasons, on truck at an indoor boat storage facility for 15 years. Stored indoors beside Aston Martin, Lamborghinis, a Lotus, and several super yachts. THAT is a sight to see.
We are in Florida and have been looking for a storage lot to drop the truck camper at (no truck under it) for 4 months starting November while we are at the condo here. Very, very few on edit: self-storage facilities will allow a truck camper on their lots sitting on jacks (ie. Not sitting on wheels).
Good luck.
Silver
2004 Chevy Silverado 2500HD 4x4 6.0L Ext/LB Tow Package 4L80E Michelin AT2s| Outfitter Caribou