I stack my boxes about 5 high and use a flat latex exterior paint. I do not paint the edges where the boxes sit on one another. That part is not exposed to the elements, so why paint it? after the paint dries I use my hive tool or a rubber mallet, every one should have one of those. If there is any small cracks don't worry, the bees will seal them if they want to. If not makes a good vent hole.
Sounds like some of you are making work where there shouldn't be any, or you just want to play. :roll: :) ;)don2