As to the closet painting, my problem with any room painting is that I'm short. Painting is not for short people. Having to put up a stool or ladder & even then reach like crazy while being afraid you'll topple off, isn't fun. Then moving the ladder/stool every couple of feet & keep going up/down/up/down while trying to dangle or balance a can of paint is no fun either.
I've never painted inside a closet. The ladder/stool situation would make it just awful.