I have always used my wallpaper scoring tool(home-Depot) then soak it with warm water. The paper should just peal off maybe using a putty or flat knife like in a drywall knife. Tell em at the H D that you need that round wallpaper geteroff -thingy and aa drywall mud putteron knife thingy and they will be able to help you. They may also sell you some watery like stuff to put in your pail of warm water.
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