Just a thought or two....Closet doors or closets not sure.
But here goes.

I own a paint sprayer and unless the house is empty you should
not use a sprayer in the house. Reason? Whether you can see it
or not the residue from the spray will travel and get all over everything.
Prep time would be the same if not more for a spray job and unless your
an expert you will apply the paint improperly.

Just get the right roller, an an extension pole for the ceiling, a cut in brush,
canvass drop clothes and throw away paint containers. I just painted one of
the bedrooms in my house and i never used as many coats as you say you
require. Unless your walls are in serious damage a primer is not needed.
If you get a better grade of paint two coats is not necessary. I painted
one bedroom taking my time including the closet in less than a day.

You got friends? Have a painting party. Cook some food and get everybody
cracking. It will take a lot less time to correct their errors then trying to do it all
yourself and it may be a lot of fun.

If it closet doors the whole game is different.

__________________
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