HRs are great motorhomes, I've owned two. Check for the basic stuff like leaks in the roof. Also, these are aluminum sided motorhomes, so look for galvanic corrosion. That can be bad. Other than that, they are solid units. If the appliances work as expected and you can't find any leaks there's really nothing that I'm aware of that you should be concerned about. I had a 454 in an 89 HR and the only problem I had was it was hard on spark plug boots due to heat from the manifolds. And, gas mileage sucks, but they all do.
Mark Anderson - FMCA 351514 - Louisville, KY
2007 Sportscoach Pathfinder 377DS - Freightliner XC
2006 Jeep Commander
Cricket SW3 Personal Transporter