Hawkins are a well built motorhome and the engine/tranny combination is great. The tranny is a 4spd automatic vs. todays 6spd autos but it does it's job well. My mpg varied between 6.5 and 10 mpg depending on terrain and if I was towing my trailered race car, which is about the same as todays motorhomes. I would have everything on this motorhome examined including the chassis, suspension, engine, transmission and body integrity. With the low mileage it has sat for long periods of time and seals will dry out, gaskets (everywhere) will dry and shrink, and body caulking can dry and pull away. I would also find out if the windshield can be replaced, check this shop out,
RV Windshield Replacement | Recreational Vehicle Windshield Replacement and Repair | RV Glass Solutions . I would figure on a complete engine and tranny service and replacement of all the tires.