3m makes a variety of hooks, ties, clamps, etc. that can be temporarily attached to the smooth exterior or textured interior using what they call "command strips".
I used 3 large hooks inside which worked great. I made sure to place them in areas that wouldn't interfere with closing up the camper so I left them in place. I'll see if they are still there in a couple of weeks and I'll see how easy they are to remove.
The wire clip style they sell worked great for my exterior Xmas lights. I used 3 clips along the top edge of the roof...1 at the peak and 1 ea at the corners. Rain had no effect on them.
All of these "command strip" products are supposed to release easily on command and leave no marks or residue. Can be found in many stores.
I tried the hangers in my TT and they worked ok until it got cold and they fell off the wall. In the spring I put them back on the wall and they stayed there throughout the summer. So I either didn't have a clean surface when I attached them or cold weather does effect them. They do work good and I like that you don't have to put holes in the wall.
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2021 Apex Nano 191RBS OFF GRID
2017 Chevy Colorado Z71 4x4 3.6 L