In Oakland County, Michigan, some scammers are working hard to make sure their pockets end up delightful this holiday season.

"I imagine they're well into $1,000, $2,000, $3,000, doing this frequently," Tom Jones, owner of Funky Monkey Toys in Oxford, Michigan, said.

The toy store has been open for over 15 years.

On Black Friday, the business experienced a first: someone paying with counterfeit cash.

"[A] $100 bill and they've bought $20 worth of merchandise, meaning they got about $75 of real money back," Jones explained.

The counterfeit marker didn't tip employees off about the situation. They realized they'd been duped when the money was taken to the bank.

"It happened here four times that I know of in Oxford. It's also happened in Lake Orion. I don't know if it's the same person, individual, or group," Jones explained.

Oakland County deputies are looking into the situation. Aside from counterfeit detection pins, officials advise checking the texture of the bill. If it's slippery, it could be fake.

"Hold it to the light. There's a watermark in bills. You can buy an inexpensive UV light. And UV lights will tell you very specifically, each denomination has a specific color, so, for example, a $5 bill is blue," Oakland County Sheriff Mike Bouchard said.

The bills used were purported to be older $100 bills.

"This is just my guess; they're actually using money paper, bleaching it and putting imprints on top," Jones said.

Since Black Friday, businesses in downtown Oxford have been on high alert.

"It's almost like an insult to these businesses. We support this community, and the community supports us," Jones explained.