I left a lot of stuff that wasn't worth the headache of removing without possibly damaging the camper. Paper towel holder, hand towel holder and toilet paper holder in the bathroom, a shoe holder (that I had mounted behind the toilet to hold small items like shampoo, soap, bug spray, etc), bed spread, some magnetic cell phone holders that I had mounted by the bed, new curtains that I had replaced the crappy stuff that came with the camper, etc. New TV and remote that I had replaced the Jenson 12v tv with. It all stayed.
I took the stuff I felt like I could use in the new camper and was easy to remove without hurting the value of the camper.