I'm looking to buy a '99 E39 523i, with mileage of about 170K. Jusy wanted to check is that high or acceptable. That is about 28K km a year. Don't want an underused car too. Something Daredevil said on one of his post, about getting a older car about more than 5 years. Where most of the parts that have fail would have failed and replaced. Also I believe that at 140K km, that car should have went through a major service. So my question is, Is mileage a very important issue when buying an used car? And how much is the average mileage a year?