A Georgia woman is behind bars after allegedly stealing two cars from a Cobb County dealership using a scheme that manipulates credit card machines.

Authorities say 23-year-old Jennifer Gibson also worked the scheme four different times at public stores racking up more than $17,000 in gift cards.  Police are still looking for her brother, Justin Gibson.

Gibson was arrested in Clearwater, Florida after authorities there caught her trying the same scheme to rent a condo.

"She found a way to force the transactions to go through on the purchasing end ultimately to be cancelled by the bank some time later," said Gwinnett County Detective James Flanagan.

Dan Dixon owns the First Financial Services on Canton Road where Gibson allegedly stole two cars.

"I'm thinking I've been scammed for about $50,000," said Dixon.

He says Gibson and her brother came into his dealership last month to buy a Range Rover.  Dixon says Gibson's check card was run and it was declined.  He says she then pretended to call the bank to get a code number to put into the machine.  Dixon says she did and the machine approved it.  Next, Dixon says Gibson and her brother bought a second car and drove off.  It wasn't until the next day Dixon realized the money wasn't in his account.

"I've been in this car business many many years, seen a lot of stuff, but I haven't seen this scam before," said Dixon.

Authorities say she was also making duplicate titles because one of Dixon's cars popped up on Craigslist.