We bought our Four Winds used - two years old with 5,800 miles on it. I suppose we should count ourselves lucky as we have not really had many problems.
Sure there are a few things, such as the crank falling off the antenna. But that is really an issue with Winegard not Thor. In fact, it has fallen off twice. Simply the setscrew loosens. Perhaps a bit of Locktite is in order.
We have had some trim issues as well, which required fixing, a busted trim piece on the table, a sloppy installed slide out switch, and some vinyl flooring coming up around the edges.
While I agree that we should not have to fix these things, especially those of you buying new, luckily mine have all been minor.
The thing I have realized with boats (have owned several - as large as 32ft), and now RVs... if you are going to use them, you are going to break something. It used to be with one boat - we called it "Jinxed", we had to stop by the parts department each time we returned from an outing.
Again, this should not be happening, but we just realize you are gonna need to fix stuff.
Now, simple stuff I can write off, but major stuff, like a bad transmission - that would really upset me.
The only thing that works on a RV is the owner...