Not sure which forum to post this in but I feel more comfortable with group. I am considering placing a decal with my photography logo on either the side window or on the TC itself (it is plexiglas). ...
I do like the removable sign idea to remove when we are away from the rig. I would make it small and put it in the window of the camper.
We usually avoid big cities and camp in remote areas near smaller towns. Still, people get tempted. The gear is insured but what a hassle for replacement. I take the media cards out each night so I wouldn't lose images but still....