Here's some of the better sites I used to visit when I owned my pop-up campers...
PopUpPortal - Index
Pop UP Times Arvee Club - Powered by vBulletin
Just keep in mind that once you camp in a pop-up, the next step in the evolutionary chain will be a travel trailer. I guarantee you'll be in a TT within two years. The final thing that convinced me to get a TT was the set up and breakdown of a pop-up.... it's a pain in the butt. Even if you're good at it, it takes at least 20 minutes to do it right. If you're doing it at night, you get bitten by a thousand mosquitoes. If you set-up or fold down in the day you sweat your @$$ off. If you do it in the rain you get drenched. Pop-ups are great in ideal weather conditions, but if it's cold you're gonna freeze. If it's hot you're gonna sweat. Canvas is NOT very good at insulation, so forget about the heater and AC in a pop-up, because their affect will be minimal, at best.
If you only have one child, you might want to check out smaller, light-weight fiberglass trailers like a Scamp, Casita or Boler. These trailers will sleep a small family quite easily and they're small and light. All of them have heat and many have air conditioning, too. If not, you can install a cheap room air-conditioner and you're good to go. Most fiberglass trailers are only 13 or 17 feet and they're so light that you can pick up the tongue and move them around by hand or with a cheap trailer dolly.
The below site is a great resouce for info about fiberglass trailers...
FiberglassRV (Powered by Invision Power Board)
I've also owned a U-Haul 13ft fiberglass camper, too. I think a small, fiberglass TT might be a good compromise between a pop-up and something like a 27 foot travel trailer. You can find 'em cheap if you don't mind buying a used trailer. Oh BTW, I've also been a regular poster at all the sites I mentioned and there's wonderful, helpful folks at all three of those sites.
Good luck on your quest!
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