A Missouri mom learned the hard way that sometimes it really is too good to be true. The Eureka resident took to Facebook to explain that a $100 dollar bill left on her car's windshield was actually a frightening scam to lure her out of the car.

It's an old trick that's often touted as urban legend: you get in your car, realize a crisp $100 bill is just outside of reach on the windshield, and when you get out to get the bill, the nearby carjacker jumps into action and takes your car. Kyri Viehman says she was lucky she didn't notice the bill until after she left the parking lot. "I pulled over to the side of the road to retrieve this miracle money that came into my life at the perfect time... I opened the bill, and it read something similar to 'Ha you thought this was real didn't you?'"

When the incident happened, the young mother was Christmas shopping with her mother and son. Now, she's warning others to be aware of holiday scams, and to always be wary of their surroundings. "Everyone just be careful and be smart with your actions. Be aware of your surroundings at all times, and if you feel uncomfortable, ask for someone to walk you to your car. Stay safe out there. I never thought of something like this happening around here, much less to me." ABC reports a few years back the Prince George’s County Police Department in Maryland got a report of a similar incident from a resident. In response, Baltimore Police warned the community of car and parking lot scams. “We have seen incidents where auto thieves will bump the back of someone's car in traffic. When everyone gets out of their cars, a thief will jump in the victim's car and drive off,” a police department spokesman told ABC.

Another car scam Maryland police warn about is when someone asks for money to repair a dent in your car in the parking lot. Police told ABC oftentimes the job is shoddy, or that the person will demand more money than was agreed upon.

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