Most times it's much cheaper to just rent a hotel or motel room instead of renting an RV to stay in.
With an RV rental you have the cost of the RV rental itself and then you also have the cost of renting a spot in an RV park for the length of your stay.
The RV spots are from $20.00 to $50.00 per day depending on the size of the RV and the hookups you need.
I prefer staying in an RV though because I don't have to deal with housekeepers coming into my room or having to check out at a certain time.
But if you're looking for it to be cheap then the hotel or motel would be the way to go.