If a debt collector comes calling, you should go researching. That's the new advice coming from Yahoo! Finance to avoid getting scammed.
Even if you get swindled, you're still on the hook to a real debt collector! That's the law.
One way to spot a fraud is to look at how old the debt is. If it's 10 to 15 years old, chances are there aren't grounds for a lawsuit.
Mandi Woodruff of Yahoo! Finance recommends, "Another way you can tell if you're dealing with a fraud or not is to look at the name of the debt collections firm and see if they include their license ID number. In many states debt collectors have to have a license in order to operate. Chances are if it's a fraud they haven't gone through the trouble of getting a license at all and they also won't give you their ID number."
You can also ask for a debt verification letter to make sure the debt collector is legitimate.