We have just started painting our very old formica counters. We started with an old based primer after washing the counter and letting it dry. We then painted with a Ralph Lauren paint and it looked great!! Then we applied a water based polyurethane and it didn't look so great anymore. Every brush mark is seen even after sanding lightly between each application. The first application was with a brush, and the next two were with a sponge type applicator. We are at a loss and are about ready to give up and just get a new counter, but we really cannot afford that right now. Any suggestions? Should we start over from the beginning? Any ideas will be greatly appreciated.