Renting an RV in Reno isn't the best way to go ... rental rates are very high and they tend to sell out early anyway. Many people who do rent in Reno arrange to do so on their way home from the previous year.

I've been renting in Vegas for the past 7 years (this will be my 10th overall). It requires an extra couple of days for travel, but that gives you a chance to acclimate to the desert on the way up and decompress (as you clean out the RV) on the way back. Unfortunately, other people have started using this route, so the RV rates are moving up, though still not as high as Reno or SF.

Put it like this: if you KNOW you like desert camping, want to acquire tents, sleeping bags, coolers and other gear, don't mind heavily used porta-potties, can live without a kitchen for a week and are willing to wait on long lines for ice, and are sure you're going to want to shower in the afternoon, then tenting might be for you.