We just moved into an old house and are repainting EVERY square inch. It is taking FOREVER!

I need some tips on how to be a better, more efficient painter. Right now we are repainting all of the trim and doors.

The windows are proving to be the biggest time suck - the outside window trim has been painted, but the mullions and shashes are still the original dark stained wood. It is taking me 5-6 coats of a Paint in Primer in one. I have tried to use a small roller on the bigger parts of the window trim, but it is impossible on the small mullions and sashes.

One room has 8 windows! This will take me 4 months to paint! Do you think I could use a spray paint primer to coat the smaller mullions and then paint over it with a brush?