Doors and Windows - Painting and Exterior Door

I am trying to help out the widow of my best friend by doing some maintenance on her house. She has a exterior door that her late husband painted on several different occassions and the paint/ stain will not stand up to the sun and ends up fading. The door gets full sun for most of the day and it is a synthetic material so the stain does not penetrate. Can you recommend something for me to do when I paint/stain the door this time around. I appreciate any help I can get as I would like to do a good job on it.

hey, does the door u r working on have alot of dips, curves and hard to reach corners? if so what do u use to get at them. i tryed to use a dril bit that has sand papper on it but thats not really working out.

Paint would be the best exterior protection for full sun. Light colors fade less than dark colors. Top quality paints give the best results.

Hope this helps.