I've seen this done many years ago by a guy who did all sorts of jobs where I lived. My dad caught him painting his boss's roof and he was watering down the paint. We've had a hard time trying to get a painter for our house. We've had a guy that had been remmended by a neighbor and he hasn't showed up to paint for 2 weeks. I want to call him and my husband says no. I'm 69 years old and I'm about ready to go and paint our 2 porches, I've painted all my life and all the inside of our home. Maybe that's the way it should be with everyone that can paint pretty good.