Grit said "But it’s your decision ultimately, not ours. And everything isn’t doom n gloom. Plenty of RVs get used every day without getting messed up.
The majority of them, I’d imagine."
I suspect the VAST majority of "RV used by someone else" situations end up without the slightest hint of trouble, either with the RV or with the relationship.
...that being said, in my non-internet life over the past 18 months, I've had 4 matters where an RV rental went bad...2 through an agency, 2 private. Worked on both the lessor and lessee side. Even with an iron-clad contract (not many of those involved), because the RV is someone's pride and joy, any dispute gets magnified beyond what it should. One of my clients complained, a bit, about "I had to pay you about half the money we got from the other guy". My answer of "I wouldn't have even charged you for me to say it was a bad idea if you'd asked me first" didn't really help.
...but in the end, it's the OP's decision.