2. For those that can't be opened with a hair dryer: first soak the small advertisement in hot water with a rag and wipe off the paper part. Then dip a dry rag in the waste oil of the range hood and slowly wipe off the rubber bottom (the waste oil can dissolve the rubber bottom). Then use detergent to wipe off the oil on the surface of the car door.
Prevent posting advertisements on the door:
1. Buy "sticker remover" and "small advertisement protector" from Taobao, clean up the small advertisement first, and then spray a layer of protector, and the advertisement will never stick again.
2. Give advertisers a place to post advertisements. The job of a poster is to post advertisements. Maybe they don't care where they put it. If you give them a place, maybe they are willing to stick it where you guide them. The method is simple. Stick a big piece of white paper on the wall next to the door and write "Please put the advertisement here" with a marker.