My wife took our Buick Verano in for a tire repair and came out with a $600 bill. The tire needed to be replaced, ok, $200. But then she agreed to routine maintenance and shown a price of $189. It came to almost $300. Included in that was an oil change and tire rotation. Then she was charged another $60 for guess what, another oil change and tire rotation. Next line, Certified pre-owned service, yet another oil change and tire rotation, this was "no-charge", and billed to the warranty. So, according to the bill, three oil changes and three tire rotations; two we paid for and one paid by the warranty. Sadly, the very positive buying experience we had when we bought the car was ruined by a rip-off con artist in the service department. GM should investigate this service department for warranty fraud! Run, don't walk, to another service department. This one cannot be trusted.