When taking off corner wood trim the paint and top of drywall paper is coming off. How can we fix this without costing too much? The area is about 4 inches by 3 feet.
Prime the area with any good interior primer and let dry. This will seal and stabilize the surface.
Now you can use drywall mud to cover the area. It will take a couple of thin coats. Sand smooth then re-texture to match the existing wall surface. Prime the repair then paint or touch-up the area with the original paint.