How big do you need? I started with a converted ambulance (basically halfway between a class B and Class C) for dirt cheap. it was made by the same people that make Chinook brand RVs and was actually quite solid (no leaks ever, despite being a few decades old, due to virtually seamless fiberglass construction). Not bad for a couple people and a dog to travel around in:
Built it myself for about $1500
And of course, it looked it. But with 3 people and a couple dogs, it became too small, so we moved up to a '72 Winnebago:
Picked it up for $2500 and redid the interior a bit with new fixtures (cheap), pergo flooring, and a bit of new upholstery. Unfortunately, as cool as it was (and it was a conversation starter everywhere), there was just too much wrong with the fuel system and the two big rusty gas tanks. Even with removing them and scouring them out, there was always rust problems clogging up fuel filters, so changing fuel filters on the side of the road becaema routine event. Doing it twice from Hartford to Baltimore was enough. I also realized that unless you take a second vehcile, this is ALSO the vehicle you have to go shopping in, go to the restaurant in, etc. So we decided that having a tow vehcile and a travel trailer was a better solution for us, as the tow vehicle can be used everywhere.
Right now, this is the combo:
Modern fiberglass composite construction with wrap-around rubber roofing has eliminated 90% of the structural and leakage problems with old RVs. Stay away from any RV with aluminum siding and no rubber or fiberglass wrap-over roof. Other than that, most fixtures in an RV (lighting to plumbing to HVAC) is the same brand and model whether it'sa $10k small travel trailor or a $250k Class A motorhome. What you pay for is size, storage, and construction quality.
When looking at Class A's go back a couple years and for the same money get a diesel pusher if you can. If an older gas one is what your budget calls for, remember what I said about construction. Full fiberglass, fiberglass/rubber roof/ or all steel (like the '70s Superiors) are the ones to look at. If looking at Class Cs, don't get the bigger ones. A 30 ft with dual slideouts is at the ragged edge of having the chassis overloaded even when empty.
Oh, and on a motorhome, really low miles is not necessarily a good thing. They ALL tend to have low miles for their age due to lack of use much of the year, but that sitting can cause more problems than use. Besides dry rotting of tires easily (and they aren't cheap tires) the plastic tanks can become brittle, fuel tanks can get rusty inside, and the water lines tend to be problematic. Travel trailers also have issue with the electric brakes and with wheel bearings from sitting on them.
