Omaha Cadillac Saleswoman Impresses 'Secret Shopper' Warren Buffett

— -- An Omaha Cadillac saleswoman had no idea that she was selling a car to Warren Buffett, but the billionaire found her so impressive that he personally requested she deliver the new car herself.

Madison Willers, 23, welcomed a customer at Huber Cadillac in Omaha, Nebraska, in May with a smile, just as she greets all of her customers. What Willers did not realize, however, is that her customer was Susie Buffett, there on a mission to purchase a new car for her father, Warren Buffett.

"When I was talking to Susie, it was clear that the car wasn't for her," Willers told ABC News.

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Willers spoke with the woman and walked her through choosing the right vehicle for the mystery driver, just as she would any customer.

When the customer asked for Willers’ card at the end of the conversation, the saleswoman just assumed the customer was actually a “secret shopper” testing her product knowledge.

The customer came back a few days later to make the vehicle purchase, finally introducing herself as Susie Buffett and revealing the car was for her father.

"When Susie told me who her father was, I was surprised," said Willers, "I told her, 'That's awesome. Your father and I go way back.'" Willers had been Buffett's server many time when she had worked as a waitress at a restaurant in Omaha.

Warren Buffett specifically requested that Willers’ personally deliver his new car so he could say hello, and the two were able to snap a picture in front of the new car.

"I was honored and humbled that he remembered me and wanted to say hello," said Willers.

Warren Buffett ultimately wrote a letter, on Berkshire Hathaway letterhead, to the General Motors CEO Mary Barra, praising the saleswoman for a job well done.