But he owes you for fees paid this year right? So hold his receipt until Feb 2014. You can tell him that you are holding his reciept and you are looking forward to full payment. It's all how you word it! For example "I'm sorry, but I will not issue your receipt until you pay your account in full" opposed to "I am holding your receipt. Please forward payment for Jan XX - Feb XX' It's true, you're holding their receipt! Until FEb 2014. Sometimes if we play with people they end up paying.

Good luck, I hope you get your money out of them.

These are good lessons to learn that make us much better at what we do.