I have bought all my RVs from private owners. I find that a lightly used "quality" unit represents the best value proposition. They are out there as many buy on impulse and seldom use their trailers. You may want to drag a friend with some knowledge along for your first look. Increasing your knowledge will happen real quick whether you buy new or used.
I've never been burned buying used but I can fix issues myself. Look inward, if you have no mechanical ability, no tools or no place to work on a trailer then maybe a new unit with a warranty is the best way to go. The trailers I bought were not trouble free and if I had to pay $100+ per hour to have them fixed then things would look different.
Good luck and have fun looking. Spent a week in Alexandria last summer and really enjoyed myself.