Representatives of the BBB say they've been getting calls from people who have fallen victim to what is now known as a puppy scam.
People will put an AD out for a young dog, get a call from a someone acting as a TTY operator, which is a hearing impaired service, and they will ask for your information so they can send you a check in the mail. The problem comes when you give out personal information. Not only will you likely get a fake check, but you could also lose your identity.
The BBB says scammers are using fake TTY services because it appears to be more reputable, but beware of anyone who wants your information over the phone or through email.