Ok here's the set up. Have had this account for a few years. Customer has kids. At first, kids would always leave their toys in the yard. After a few cuts, I had trained the customer to have the yard cleaned up before I arrive. Only a few times since I would have to remind her of stray toys left in the yard. Well, I was mowing yesterday, and ran over a tennis ball. Never saw it. Busted out a window. Who's responsible for replacing it??? And yes I have GL ins, but it's a matter of principle.