If you think of an RV as an investment, you will never enjoy the lifestyle and joy that it can bring.
Take a cruise, or a flight somewhere, anywhere, and then calculate how much of the cost of that trip was recoverable. See if you can get back the cost of the hotel, rental car, meals at restaurants, etc. Your total expense of any trip, that is not done with an RV, is gone forever. It has no resale value.