Jack Metzger's post points out something I should have mentioned.
The absolute best buys to be found are often older higher quality travel trailers that were purchased new by older couples who could afford them. That type of buyer often knows what they want, buy it, and take excellent care of it for years. They buy quality, don't have children, and don't abuse or neglect the trailer.
Sometimes they upgrade to something larger or fancier, sometimes their health fails as they advance in age. In either case, their second hand trailers are often great buys. They will normally give you an honest description of the trailer you can trust.
Back in 2001 or 2002 I had experienced not one but two Airstreams being severely damaged by hail storms and had received insurance settlements on each and sold them in private sales.
I found what appeared to be a very nice, very clean, 1987 Avion 32' travel trailer for sale in northern IL. It was advertised on an internet classified ads site. I called the owner who was retired from Caterpillar. He had bought it new and used it gently and had to sell it due to health issues.
I agreed to buy it without seeing anything more than three or four crude photos and immediately sent him a check for $1000 to show good faith. A week or so later I drove to IL and met him at a local RV dealer's lot where the trailer was consigned for sale. It was precisely as he had described it, perhaps a bit better. I handed over the cash, (illegally) hung my Texas trailer license plate on it, and continued my journey into New England.
It was a beautiful trailer in perfect condition except for a crease on the rounded roof edge on the street side where he had hit a gas station canopy. I knew about that.
I pulled that trailer more than 60k miles in two years including a trip to Alaska. I loved it. I replaced all the appliances (myself) and made some improvements thinking I would keep it for many years. It "shrank" on me during a seven week Alaska trip and I got the bug for a fifth wheel. I sold the Avion for nearly double what I had paid for it. A broker from NM came to Lbk and bought it from me for resale to a bunch of weird, dope smoking hippies who lived on a mountain in Colorado.