$1500 is a premium price but if the fiberglass and tent are in good shape and it truly has all the accessories it might be a nice one. The $200 one in Denver is for a full size, they have a smaller market and always go for less than the ones that fit the 6' mini truck beds.
FWIW, the accessories that you look for are the kitchen organizer (a panel that fits in front with a bunch of pockets), gear loft that hangs over the bed and rear door (a velcro-mounted tent-like zipper door you can install so you can leave the tailgate and lift window open). The camper should have a mattress, curtains, two fiberglass poles that hold up the roof, two outrigger poles (we call them anti-sea sick poles) and two brackets that hold out the little vent windows, those are not accessories but original parts.
