Some rapairs I did to the door panels before paintng them:









The original texture - exposed to sunlight - goes dead and just scrapes or sands right off. Where the 'dead' layer meets the parts that weren't in the sun, you have to feather them out in order that the texture will cover. IT was a major PIA, and with 8 cans of paint, plus other stuff, it'll be like $200.00 in materials.