MT. PROSPECT, Illinois -- On a recent Tuesday afternoon, Mt. Prospect Paint owner Bill Lagattolla was selling considerably more Lee DeWyze T-shirts than primer or brushes. And that was just fine with him.

"He was our top sales guy," Lagattolla said proudly, referring to the "American Idol" finalist's skill at selling paint, though he might as well have been talking about T-shirt sales, since the store had already sold thousands of the neon-green "Be-Lee-ieve" keepsakes over the past few weeks. "[Very] personable ... he was really good."

DeWyze began working at the store when he was 15, around the time he first began fiddling around with a guitar, and he stayed on the payroll until he was 18, leaving for a short time and then returning three years ago. "[He started playing guitar] shortly after he started," said Lagattolla, who gets hundreds of phone calls a day from curiosity seekers looking for information on DeWyze. "When he started working, he [needed] money for guitars and strings, and that was one of his thoughts of working here, so he could buy things he wants."

A quick study, DeWyze's specialty was stain and paint matching, a skill Lagattolla said is very hard to master. "Anything Lee did, he was always very competitive and wanted to be the best," he said. But it wasn't all work and no play. As DeWyze was working on mastering the guitar and writing his first batch of songs, Lagattolla said he used to bring his guitar in slow Sundays, often improvising lyrics about his fellow staff and the customers to pass the time.

"When he worked here, he worked for necessity," said Lagattolla, who proudly displays a photo of Lee near the register and a giant sign over the store's front window that reads, "Mt. Prospect Paint Congratulates Its Very Own American Idol Lee DeWyze."

Because of the exposure he's gotten since DeWyze rose to the top three on "Idol," Lagattolla is used to the attention in the store. During MTV News' visit, no less than half a dozen families and friends of DeWyze came in to buy shirts or just chat Bill up about Lee, often sharing stories of when they first saw him perform or asking Lagattolla what the singer was like when he wore an MPP employee badge.

After leaving for a few years, DeWyze came back when he turned 21, and Lagattolla said he could sense a new maturity in the singer, who was then preparing to release his debut album, 2007's So I'm Told. "He definitely had gone through a few things that made him stronger," said Lagattolla, who divulged that the pair liked watching cooking shows together on the store's flat-screen TV and that Lee's favorite color is a kind of bright orange called tangelo. "He had a new goal in life ... to get stable and to start working ... really chipping away at his music career."

DeWyze kept the gig right up until he left for the Hollywood rounds of "Idol," and Lagattolla actually kept him on the payroll -- at $500 a week -- until the top 10 since Lee didn't have any other income. In fact, Lagattolla said, Lee is still on the store's health-insurance plan, though now that he's on the verge of possibly making it to the finale, he might be able to afford his own coverage soon.

"When he worked here, he enjoyed his job," his old boss said. "Lee is that kind of person. When he's into something, he's full bore. But definitely his passion was music and singing. ... That's where he wanted to be. So 'American Idol' has given him that opportunity to do it."

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