Keystone Bullet Colt

Looking at getting back in the "game". Been tent camping for last 7 years, loved it but a small trailer is a nice option at 67.Jettisoned the big trucks years ago, but I can tow a small trailer. Any thoughts on small used trailers, what to look for etc. I'm looking at 4000 or less dry weight.My last TT was a 2002 Holiday Rambler. A lot has changed. I am looking at a Keystone Bullet Colt.