The rub about warranty repair is that, depending on time of year and Dealer Service Dept., your RV can sit at the Dealer for a long time. That is certainly a loss in the $ column.
If buying new, I would select the frame, running gear, and fitment as my first criteria. If I had to pay a bit more for a more rugged trailer, that would be an easy decision.
There was a reference to tongue weight and that is to be considered with a light vehicle towing. You want to have those vehicle payload numbers in mind and make sure your tower is outfitted correctly. THere are many threads about owners or potential owners choosing too much trailer to pull.
An RV isn't a Space Station. With a few hand tools, some knowledge, and the will to work/improve, anyone can maintain an RV. The roof and exterior openings need to be sealed thoroughly and not allowed to leak. Beyond that (and Eternabond tape will get one beyond), it's typical fixums inside. A knowledge of the braking system, axle bearings, and spring suspension is a good thing to have. These will need some maintenance but a rookie DIY'er can tackle them, also.
