I have a 1975 class C.
As Chum Lee points out, you're paying for it either way.
I tend to look at my clipper more as a "house" purchase than a "vehicle" purchase. Meaning, when things start needing repairs, I repair them knowing they will be fixed for another X years. I don't sell my house because the water heater went out, so I don't sell the RV when something goes out.
And, even with a rebuilt engine, new carb, and new fuel tank, I have still put out less money than I would have spent buying a new rig - which would likely have issues needing to be dealt with under warranty.