Hi. One of my customers has asked me to kill off the moss on her lawn to let the grass come through. The worry I have is that the moss constitutes a substantial part of the lawn and if I kill it off, there may be very little lawn left. The best idea I have come up with is to treat it with one of those "Lawn-builder" treatments that kills moss and weeds while also planting grass seed. I suggested to her that we should try a sample patch of the lawn first to see how it goes. Any helpful advice from anyone would be greatly appreciated.