if you include maintenance and depreciation of a new one, sure. if you bought a used but very well maintained one and were able to do most repairs yourself and get free fuel, then its probably closer.

It can be, parts for RVs can be very expensive. I paid over 400$ for a new water heater for mine. And we were just living in one while we built our house, no engine maintenance required. Also god help you if the onboard AC breaks. Difficult and costly to fix.