You can check out my review of 1999 Saturn SL-1 for an example of some things that needed to be replaced on one that I bought for my wife with 103k miles and which we kept until 120k miles, when I bought her a Jeep Liberty. Basically things to watch out for are typical: upper engine mount, basic maintenance, etc. One thing you might find you need to check is the transmission valve body, by this mileage most originals are worn out and the "reverse slam" can cause other transmission problems in the Saturns. The fix is not hard, but not cheap, either -- replacing the valve body with a rebuilt unit.
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