I was trained as a mechanic in the Marine Corps. and have a life time of working on cars in my background. With vehicles, major mechanical issues will generally show up in the first 10-20K miles. Most major recalls happen in that kind of time frame as well. After that, you really are talking more about regular wear and maintenance. We bought a Chevy Prizm as a prior rental with 40K miles. It is about to roll over 150K miles. Two issues have cropped up in 10 years of ownership. Failed power steering pump and pressure hose. Failed A/C. The drivetrain has been totally reliable.
As to the coach part of an RV, that has to be gone through with a fine toothed comb. Remember that it's a house on wheels. House "types" of things often go wrong without people knowing and lead to very unpleasant discoveries. I am doing a cabover rebuild of a 1983 class C and am realizing these things are built very boat like. That's another environment where small things ignored become very expensive repairs down the line. You have to be meticulous in checking every single seam and water fitting for leakage or water damage on a class C. If you buy a rental, they have usually been looking in all the known areas and sealing up any leaks they find.
I don't see a lack of extra's on a rental as a major down side. You can add on most anything for not too much cash and less farkles means less holes/seams where water could have come in before you own it. Less farkles also means more room to haggle the price down. I think slides are super cool, but again that is something else that can go expensively wrong.
Overall, I would consider a well running rental RV with no more than 50K on the odometer and full service history as properly broken in. I would also not be bothered by a lack of extra features as they can all be added fairly inexpensively by a competent DIY'er.
That's MY opinion. ;-)
Jose
