Christopher Runge thinks he's good at making money. After all, he turned $5 into $100.
The trouble is, he's did it by making counterfeit cash.
"Gas stations, laundromats, restaurants, wherever -- we were buying more supplies to make more," Runge said from behind the glass at the Denton Jail. "(We were) buying phone cards for phone time for talking to people, just clothes, jewelry, whatever we wanted."
Runge told NBCDFW he probably spent near $10,000 in fake cash.
He even bragged about how good the bills looked.
"These bills here are good enough that I think they could have passed," Runge said. "Some of these bills will stay in circulation for quite a while."
Detectives said Runge and his roommates would wash $5 bills with a solvent to remove the ink. Once the ink was gone, they would use a printer to transpose the bill into a $100 note.
If a cashier tried using an anti-counterfeit pen, the marking would indicate the bill was legitimate.
When asked why he did it, Runge said the answer was simple economics.
"We were needing to pay rent -- (the) economy's down," he said.
Police were tipped off when the roommates tried to use three fake $20 bills at a pharmacy. The bills were lower grade, and the cashier called police.
Capt. Lenn Carter said surveillance video of the transaction led detectives to Runge and his roommates.
Runge, Carson and Gibson face state charges for counterfeiting money and could face federal charges.