How about truck+trailer combo. The vehicle can be used without taking your house everywhere. And the reliability of each of these things alone is higher than an RV
35ft fifth wheel RV: Truck burns 14 MPG on a good day. Tires $1000+ every 30-50k mi. 6-9 mpg towing if using gasoline
Now do the math on driving your RV everywhere (or purchasing a separate smaller vehicle that you can use to get around town, and tow behind the RV when traveling). I'd assume that would cost more.