Junior’s Building Supply, in Ringgold, Ga., likes to keep an eye on its customers—literally. The two-location dealer employs nearly 70 security cameras at both its retail location and its warehouse.

Owner Otto “Junior” Boehm Jr., says that he has gradually been adding cameras to his “homemade” security system since he opened the north George company in the 1990s. Junior’s employs 40 and reported $21.5 million in sales in 2012, about 80% to pros. Boehm expects 2013 sales to hit $25 million.

The Georgia dealer keeps watch over its operations using an extensive network of security cameras, including 51 at the Ringgold retail location and another 15 at the warehouse. “We sit here and watch them, and they sit up there and watch us,” Boehm says, chuckling.

But in all seriousness, the network of cameras does help Junior’s track down bounced-check writers and prosecute thefts.

Cameras over the registers monitor every transaction. When the bank returns a check for nonpayment, Boehm reviews the past two months of video to the exact time the check was written. He captures the image of the check writer and sends it to the police.

Repeat offenders get their picture posted on a bulletin board. “Once we catch someone stealing once or twice, we put their picture up,” Boehm says. “They rarely show up again.”

A man once came into the store and berated Boehm for not having enough corner bead for drywall. On his way out of the store, he grabbed what corner bead was there but didn’t pay for it. The next time the customer came to the store, Boehm asked how many pieces he had taken. Surprised, the man admitted to the theft and paid. “Kind of wiped the smile off his face,” Boehm says.

The company uses the video evidence to prosecute shoplifters and bad-check writers. If a police officer pulls someone over during a traffic stop and discovers there’s an outstanding warrant for writing bad checks, Boehm says, “they just take them to jail.”

Junior’s uses cameras from, and online monitoring through, a company called WatchNet out of Tonawanda, N.Y. WatchNet’s online access to the video system allows it to check whether the triggering of a late-night burglar alarm is an actual break-in or something less threatening.

The cameras themselves are a combination of older analog units with several newer digital high-definition (HD) ones. The storage equipment can save up to two months of video, though that will likely shrink in the future as HD video takes up more memory space on DVRs.

The camera system not only monitors thefts but also tracks employees “to see if somebody’s somewhere they shouldn’t be,” Boehm says.

With workers’ compensation claims, the company will review the video to see if the injury occurred as claimed. Boehm has even caught employees sleeping on the job, smoking, and pretending to work. “We have about six live cameras,” Boehm says, “that we can flip down to see who’s working and who isn’t.”

A few weeks ago, a woman came into the store to report that her husband thought he’d lost his wallet there. Boehm tracked the man’s movements from when he entered the store, stopped to get coffee, returned some merchandise, and left. Nowhere along the way had he left his wallet. While the cameras didn’t help her find the wallet, they did at least show where it wasn’t.

—As told to Steve Campbell