I've got 215K on mine and it's still going strong. If it's a clean, well maintained car then $5K is about right. The car has several maintenance areas that you should plan on doing over the next few years, but most are DIY's at reasonable expense. Definitely get the PPI and look at the history. Probably the biggest thing to worry about is the clutch which is pricey and hard to DIY. If the subframe is cracked or hasn't been inspected you may want to pass.
2003 E39 M5 Lemans Blue: The most amazing car ever built
1999 E46 328i Bone stock 5-speed: Soon to be track rat
235K and still running strong