This is a fake check scammer who sends you a check for an amount more than what you are asking for your Craigslist or eBay item. Then asks you to wire them the difference. By the time the check bounces, he is long gone and your loss is whatever you wired him. If you get contacted, play along and allow him to send the check. When you receive the fake check, just tell him the check bounced already. This will tie him up a bit.
scammer's number: (917) 765-6038 - he only texts, will not answer phone calls.