Hi ETA4, thanks for your review. I'm sorry to hear the water stains are showing through the paint after 3-4 coats. I can understand your frustration, and I want to help. To fix this, I recommend priming with our Multi-Surface Primer to block the yellow water stains. Then, you can apply our Premium Plus Interior Flat paint No. 1050, which has more paint soiids to provide better coverage. Customer satisfaction is very important to us, so feel free to reach out to our Customer Care team directly for further assistance. They are always happy to help. Enjoy the rest of your day. -Christina