Revisions log for Answer #2908

Yes, if you sand, you don't need a degreaser as far as I know.

I have always gotten by without sanding in my recent painting activities. On one thing, I think it was plastic boards on a balcony, I needed extra primer. That's where I would double check what it's for and possibly use it in one coat before painting. I would work on the doors as well as frame with foam roller. If there are a lot of corners, pre-paint with a small brush and finish with a small roller.

Remember the rubber lips – if you want to do it right, change them after painting :)

If you are sanding, you could also glaze – that will preserve the grain.