Ok, a new customer sends me an email, after I call him 10 days after his due date to ask him where my money is. The letter basically says " I am sending you a check for last month's service, but I was shocked to see that you are charging me sales tax. This is not the price I agreed to, so I deducted the tax from the bill and sent you a check for that amount." After that he threatens to cancel if I can't provide service "for the agreed price" WTF?? This guy is trying to play me for a chump. I have not called him yet because I want to tell him what a moron he is, and I am seriously considering just dropping him. I want to be reasonable and not get hot over the phone because I just sent out my bill for May. My dilemma is, I need the account, it pays well (although late). It consists of 3 lawns that I make good $$ on. Very easy, quick lawns. I know this guy is a jackass, but I want to salvage the account. How would you handle this?