Thinking of buying an RV, looking for advice/wisdom

Since you'll be alone for much of the trip, I'm going to suggest you look at a small towable like a teardrop or scamp. I'm not sure what the towing limits are on your SUV but if you stay within the limits your depreciation value shouldn't change at all.

As far as friends joining you - let them bring a tent. You can cook on your burners for them or provide a dry place to sit for awhile during a storm but why buy a bigger rig just for a few days of visits?