I have just recieved a check for a job I did a few months ago. As excited as I am to get paid, this is actually the second cheque for that job, so I have been paid twice for one invoice. As much as I would like to keep it, it is not my money. I have already been paid for my services when they sent the first cheque. So what is the proper thing to do? Can I just tear it up? or frame it to hang in my office? Do I need to mail the cheque back, and pay postage, an envelope as well as my time. This has actually happened before (with a different customer) I called the customer and ended up returning the cheque.