I have had something similar happen in the past. I had a border collie that needed a home, and went though a rescue organization, and email lists where I felt like I knew people. Someone turned up a couple in Florida who wanted my dog, and wanted me to ship him, and promised to pay me more than just the shipping fee. Their check bounced (but I hadn't shipped the dog yet), and they apologized, and asked for my bank routing number to send me the money. I couldn't think of why they would need my bank routing number, and said they could wire money to me through any of the standard services, and I would pick it up. Of course they never did. There are so many ways people can and will try to scam you. If something doesn't sound right, it probably isn't.