When I was visiting my sister in Chicago this weekend she couldn't say enough about the great customer service she has received from her BMW dealer -- emphasis on her .

She repeatedly referred to “Knauz BMW” as her dealer. That store took the time to form a relationship with her, she said. She doesn't want to go anywhere else for service, and the next time she's in the market for a new car, she's going to Knauz.

She describes her experience there as “just like personal banking.”

The clincher? Knauz's employees won her trust. It all started in the service department.

Here's what she said made the difference:

• They performed a thorough inspection of her car.

• They recommended service -- they didn't aggressively sell it.

• They provided her with a free service loaner while her car was in the shop.

When she asked if she should invest in a new set of tires, the service writer recommended it after examining the tires for wear. One of the tires had a slow leak and she had to bring it in a few times to get it fixed over the last few years. Each of those times Knauz tried to save the tire instead of insisting she needed to replace it.

What got to her: He told her the car had another eight good years in it, though she bought it new and has owned it for six years.

Other BMW dealers closer to where she lives and works have courted her business, but she said they failed to provide the same high level of service. “I completely trust Knauz,” she said.

Building a strong relationship with the customer sounds so simple. But in this case, only one of several dealers was able to do it successfully.