Hello, Im new to the BMW scene and I need advice please. I am looking at a 1989 M3 4 cyl turbo with 133,000 miles on it. Its a 2dr. 5 speed, it is in great condition, motor sounds great and everthing works. This car was purchased in Germany and brought back to the us, I am dealing with the 2nd owner. Its selling for $5000, is this a good price? Is this an expensive make and model to maintain? Is there a difference in a car brought back from Germany and one made for the states? (it does pass Virginia inspections) Any subject anyone can educate me on would be greatly appreciated. Also, this car has always had 20 w 50 in the motor. Would it be wise to change to a thinner weight, and would synthetic be better?