I would consider all this general maintnace items. He sounds like he knew what he was doing.
The wheel sensor is in the wheel hub assembly, so that will need to be replaced to get the traction control light to go away. Not only will it affect traction control, but it can also turn off your abs.
Brakes and oil are easy on all cars, you may want to find a friend who knows what they are doing to give you a hand the first time, then you'll see how easy things can be.