Fixing door panels
 

Anybody good with stuff like this? My door panel upper section, right under the window are coming unglued and starting to sag. the rest of the door panel is in good shape with no stains or tears but sun and moisture have done damage to the upper part. anyway, what can i do about this? can i peel it all the way off, pull it tight and reglue it with something? if so whats good to use on this type of thing?

approx $100-$150 in our local upholstery shop.