The way most motorhome walls are constructed (laminate of thin materials sandwiching a foam core) the outer walls are not likely to be strong enough to support a TV mount. For anything originally installed on the walls, the manufacturer imbedded a metal or heavy plywood mounting plate, before laminating the wall. For stiffness, the wall will have some perimeter framing in the sandwich, and a few verticals, but this will be 1" square, not full depth of wall, usually against the outside skin so there is insulation on the inside.
There are a few manufacturers of small A motorhomes that were built with framed walls, i.e. regularly spaced studs, usually aluminum. What Holiday Rambler built for the Monaco group, and Newmar, come immediately to mind, but there may be other small volume producers that did not adopt mass production laminated wall construction.
These studs may or may not be usable for mounting. Sizes will be 1 1/4" to something less than 2", by something less than 1". From what I remember of Holiday Rambler walls in the era of aluminum skin, the framing material was a channel, heavily perforated for weight management. So even if you find a stud, you could be trying to fasten a screw into a slot or a hole in the channel.
If I wanted to carry a 28-32" TV, I think I would find a place to carry it while moving (under the bed might work for my RV) and set it up on the table, across from the couch, for viewing.
In smaller sizes, there might be a possibility of finding a spot on a cabinet that is sturdy enough to handle a TV mount, particularly if you could go through a cabinet wall and install a backing plate.
Many A's put a medium-size CRT TV in a cabinet up front. Some part of that cabinet should be sturdy enough to handle a TV mount, if the load was spread over a large enough area.
RV parks having size limits? I don't know that I've ever been in a park that would turn away a 45-footer, which is the largest coach legal without a permit on U.S. highways. In most mobile home parks, the smallest units are typically at least 40 feet long. I don't think a 30-35 foot motorhome is going to run up against size limits in those places. Campsites in older public parks, and in forests, those might be more of a problem in some parts of the country, as many were not sized for RVs of any size, rather to serve as a parking space for campers.
