I’ve written upwards of 140 posts about scams, fraud and identity theft since last July, and it seems like there are a lot of schemes that are based on the same idea, only with different details.

For example, consider these two scenarios:

1. Rental Scam: a landlord is sent a cashier’s check for far more than the first/last month’s rent and security deposit. The crook tells the landlord to just wire the overage back to him. Later, the check is returned as fraudulent.
2. Mystery Shopper Scam: a job seeker is sent a cashier’s check and instructed to cash it and wire the funds back, allegedly to check out the customer service at Western Union. Later, the check is returned as fraudulent.

They’re two different scams, but they hinge on that counterfeit check, and they both involve wiring money. So let’s extract a general rule of thumb here, a Fraud Prevention Template:

Anyone who sends you a check and instructs you to cash it and wire money back to them is attempting to commit fraud.

That’s it. If you’re in a situation that involves a check and wiring money back to the maker of that check, you’re about to become a victim of fraud if you continue. The actual context doesn’t really matter.

Someone contacts you via Craigslist to purchase an item you’ve listed. They send you a check for $2,000 more than you wanted for the object. They tell you to just cash it and wire the funds back. It fits the template.

You get a letter that says you won the Canadian Lottery, but you have to pay taxes and fees first. The letter includes a check with instructions to cash it and wire the funds back to them. It fits the template.

The best part of keeping this one simple rule in mind is that you don’t even have to carry any other information around in your head. You don’t have to know that a legitimate lottery never asks winners to pay in order to claim a prize, or that you can’t win a lottery you never entered, or that it’s illegal to play foreign lotteries—you’ve got a check in your hand, and some clown is telling you to cash it and wire the money back. You know right away you’re dealing with a con artist. Fraud averted.

I’m going to come up with a few more of these templates over the next few weeks. It’s a lot easier than trying to memorize the details of every little variation.

Don’t worry, though; I’ll still be on the lookout for all those variations to write about, too.