I never did answer the original question.
Yes, region and condition do affect prices, as does demand. Shopping in the fall or winter will often get you a lower price than in the spring and summer, when everyone wants to go camping. Prices tend to be higher west of the Rockies, due to shipping costs. A camper in good condition can easily sell above book value. Our first one did. We paid a premium for it ourselves, used it for five years, and then sold it for more than we paid for it. In a down economy, people still want to camp and travel but don't want to or can't pay to buy new, so more people are looking for a good deal on a used entry-level camper.
NADA and KBB (Kelly Blue Book) will give you the most accurate values, but their listings don't take into account regional demand. So if pop ups are in demand in your area, you may have to spend more than book value to get what you want in the condition you want.
It's impossible to give any opinion about the value of what you're looking at without knowing make, model, and year.
It's like asking what a car is worth, when we don't know what kind of car.
When you look at the camper, be sure to crawl around under it, look under curtains and in cabinets for water stains, etc. If you see any water damage, even a little bit, you might want to pass on it because it's most likely worse where you can't see it. Sniff the camper and see if it smells like mildew. If it smells like wet wood, pass. Also, before deciding to hand over your money, have the seller set up the camper and take it down, or better yet, you do it under the seller's supervision and direction, so you understand what's involved. Pop ups aren't for everyone. I've known people who have bought one, used it once, and gotten rid of it because they didn't want to deal with the set up. Have the seller turn on every appliance and light. Don't be shy to open cabinet doors. Have your entire family sit in the dinette, lay on the beds (shoes off), and imagine what it would be like to be in there on a rainy day. Look in the cabinets and think about where your stuff would go. Cabinets fill up fast. Is there a space to set a cooler? Where will duffel bags go? Where will the Porta Potti go? Is there room for dishes, pots, dishpans?
Assume you will need new tires, and also assume the wheel bearings will need to be re-packed and the lift system will need to be lubed. Neither the wheel bearings nor the lifters are hard to lube if you're handy, and parts, if needed for the bearings, aren't that expensive and neither is the grease.
You may want a sway controller to help reduce sway and make for a safer ride. We paid around $100 for ours at a dealer. We had to have it on the spot and I'm sure we could have done better buying it elsewhere, but we didn't have any choice. If you can install it yourself, you'll save too. We had the first one installed by the dealer, again because we had no choice at that time, but we installed the sway bar on the new trailer ourselves.
It will cost some to outfit the new trailer unless you have tenting gear already, but it can be done over time secondhand, most of it anyway. I raided our closets and cabinets at home for a lot of our stuff, and picked up a lot of other stuff at garage sales. Dollar stores are also a great place to get camping gear. One time, I filled the entire back of our Chevy Blazer from the front seats to the tailgate, up to the ceiling, for $7. Gotta love church bag sales! Most of it was camping gear (we outfitted two campers that year.)
