All class C's are conventional vans with everything in familiar places for a mechanic to follow "By The Book" with very few exceptions. Class C's also have all the safety standards of a van until the RV company cuts the structural roof for easy entry into the cab area from the house area which compromises roll-over protection for the driver & passenger in the two front seats. The chassis is made per NTSB standards with additional consideration to repairs, corrosion, warranty, and long term reliability.
Class A's are a different story. Though much starts out in the same place, there is much that is custom made, and even some standard things are relocated by the RV manufacture. They are NOT made to the same safety standards for frontal collision or roll-over, and they are often not made with consideration to mechanical repairs.
I volunteer
HERE at our church where vehicles are repaired for people who are financially challenged. The charity is funded through the donation of vehicles, much the same as Cars-For-Kids and Cars-For-Vets. We get all kinds of vehicles donated including class C and class A motor homes. Donated vehicles almost always have problems. One of the jobs of the volunteer mechanics is to get such donated vehicles back into road-worthy condition so they can be sold to fund the repairs for people in-need.
The class C's are well understood. The class A's require a lot of time to figure out with odd issues that are most often caused by poor wiring practices by the RV manufacture. Another serious challenge with class A's is that they are assembled with untreated steel. Brackets are often rusted to the point of bending or breaking. Another matter is that many class A's are assembled with minimal consideration to mechanical repair. Some repairs require removing fiberglass body panels held together with severely rusted steel that falls apart when disassembled. The bottom line is that they are dang hard to work on, and dang hard to fix right. You practically need a small metal fabrication shop to work on older class A's.
I completely understand why many auto shops refuse to work on class A motor homes. If I owned an auto repair business, I too would kindly wave them off. It also explains why Camping World charges so much for certain repairs.
In my opinion, the way to own a class A is to buy it new or almost new, and get rid of it before the real problems surface. Buying an old used one runs a high risk of buying a heap of trouble. Of coarse there are exceptions. Admittedly the few class A's we've worked on were not high-end units. Maybe high-end ones are different.
