When Greg Rietz walked into Lujack Northpark Plaza in Davenport, Iowa, more than 20 years ago, he was just looking for his next vehicle. Instead, he found a new job, a new career path and the opportunity to fulfill his potential as a natural-born entrepreneur.

“I was working for a grocery store and I bought a car here,” Rietz says, reflecting on his first visit to Lujack in 1989. “Now, I get here a little after 4 a.m. every day. And I do it all myself.”

Currently stationed at Lujack Honda, Rietz lets himself into the store with his own key and, while the rest of the industry is still sleeping, gets to work on the dozens of letters and cards for everything from birthdays to anniversaries that he writes every day. Then, when the real workday begins, he makes the first of an endless stream of phone calls — totaling as many as 1,000 per month — to his personal client list.

He has neither a team of subordinates nor an administrative assistant to help, which is the way he prefers it. It’s a near-daily grind that starts every Monday morning and ends on Saturday evening; if the store was open on Sundays, he probably wouldn’t take a day off. His efforts have resulted in outstanding production: Rietz regularly sells 60 units per month and has moved as many as 94. He has jokingly threatened to retire if he ever hits the 100-unit mark, a move that would likely send his bosses, including General Manager Jayson Newman, into a blind panic.

“When you’re doing your forecasting, setting up the month, you can pretty much pencil in a lot of production from him,” Newman says. “He’s consistent. You have a lot of turnover at the bottom of your sales staff. He’s a guy you can’t forget to manage but don’t have to put a lot of effort into, either. He’s extremely self-organized.”

As CRMs have come and gone, Rietz has maintained his own database of clients, which now number in the thousands. He keeps notes on index cards, marking down every birthday, anniversary, graduation and childbirth. He knows which customers have personal, financial or health concerns, and he makes every conversation revolve around them, rather than their vehicle. He follows up with every sold customer, even those who stray from the Lujack family.

“I just had a customer today who had looked at a 2012 Fit. He wound up buying it from another dealer,” Rietz says. “I called him and he said they never called him back. So he brought it in and traded up for a new one.”

“And he was an hour from here,” Newman adds. “He was only a half hour from the other place.”

In his spare time, Rietz enjoys his private collection of fine automobiles, which includes Lamborghinis, Mercedes-Benz SLSes and Dodge Vipers. A bachelor, he considers his clients his family, and they respond in kind, occasionally stopping by just to deliver plates of food from their tables. He has sold vehicles to three generations in some cases, a clear indication of a level of loyalty that few sales professionals can hope to reach.

“He takes full ownership. It’s all part of the customer experience,” Newman says. “He’s like six salespeople.”