I would return it and get a roller. I have done a fair amount of interior house painting and I can't imagine trying to do it with a spray gun once the house has been finished. I looked into the power rollers but the clean up time with these is rather lengthy. We went with a Wagner roller that you manually suck paint out of one gallon containers into the handle. It has a trigger that you use to pump the paint into the roller. It works very well and is quicker/cleaner than the old tray and roller types. It is also fairly easy to clean and at <$50 much a better bargain.