We're not shopping yet, much more of in the education mode. This forum and others have so much information about RV's so I was on a "sight seeing" trip if you will to see what I've been reading about. This particular consignment dealer has lots of brands, types and ages of RV's. MH's, 5th Wheels, TT, etc. One is free to wander about the lot and look at whatever you want, as long as you want, without a sales person in tow. And they're not too far from the house.
So this particular trip was to look at frames, tires, windows, roofs, spotting water damage (which was abundant) and so on.
To kb0zke's question, we didn't really look to see if it was on a particular brand, or frame type. Again I didn't crawl under them to see if they were U-bolt attached or whether they were loose, bent, damaged or other.