My first question would be "Why are the owners selling a 1-year old trailer?" Problems, or just trading up?
Danemayer hit the high points - especially checking the roof and tires. Even though it's only a year old if it smells musty, has water stains, or the floor feels spongy, run. This goes for any used trailer.
We looked at a used TT on a dealers lot but even though it was a year old they weren't even offering a 30-day warranty, it was being sold "as-is." We passed on it.
The 22FBS is a nice floor plan for 2 people, it's basically a stretched 21FBS with a couch. Easily towed with a properly-equipped 1/2 ton truck or big SUV. It probably comes in at 5,000# empty. My wife likes the big bathroom and all the storage space. I think the straight kitchen sink has more usable counter space than the angled one in our 21FBS.
We had the dealer make 2 changes - add gas struts to the under-bed storage, and convert the pedistal dinette table to free-standing using legs we saw in a Trailrunner SLE22. I made a few more mods here:
http://s1114.photobucket.com/user/starmaster1953/library/North Trail 21FBS
One pic I don't have is where I swapped the cabinet doors over the bed side to side, this put the hinges towards the inside of the bed so access is easier from the side of the bed.
There were a few minor issued I fixed myself, nothing that required a trip to the dealer. Overall it's worked out nicely for us.
I don't know if it's true for the 22FBS, but in mid-2013 there was a running change to the 21FBS slide. It went from a shallow, raised one to a deeper, flush slide. To do this the whole trailer was raised and it went from 2-steps to 3-steps on the outside.
One feature I wish it had was a slide topper. I'll be looking into one this spring.