No need to back roll just spray it on. Buy a graco 395 its worth it in the long run.
I assume you're changing colors in these units? If re-painting same color then you're way over-doing it to get acceptable "apartment" results. 10 years ago my wife and I did full-turns on apartments... We did the painting, she did the cleaning, and I did the carpet cleaning(with a great truck mount). We soon found out that painting was where the money was at(along with less stress) and dropped the cleaning and carpet cleaning.
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