I add small labels to the backs of our banners. Never put anything on the face side of our
signs. If it's double sided then it doesn't get anything.
All the labels are printed on removable adhesive vinyl so the customer can take it off if they choose.
I also add a label to the door jamb of all the vehicles we do. Get a lot of calls from body shops if the vehicle has been damaged and they need something replaced.
All the electric stuff gets a sticker. Some of the wall
signs have to have a permit sticker in the window with our info on it, by code, that's a little added advertisement.