Recently I sent out monthly invoices. I noticed that one of my good customers had still not sent in his payment from the previous month ($250). So, I sent the statement showing 2 months of work. The customer calls and said that he mailed the check on such and such date and gave me the check number. I asked if it had cleared his bank, and he called me back and left a message saying that it did clear his bank. This customer has an excellent payment history, big house etc.. I just don't have any record of the payment on my end. I am usually very careful in recording these things. Question: Should I ask him for some sort of proof? I hate to offend him, but.........$250 is $250 HELP!