Buy CLK 320?

Ask CLK 320 experts I’m just wondering if I should buy the CLK320 W 208 (the old box from student times is slowly getting tired).The experience with the 320 sound positive, and a purring six-cylinder is very tempting. Now my question: which parts are vulnerable and what should I consider when buying a used one (built in 98 or 99)? Are there children’s diseases? Are 18000 euros too much money, (for leather equipment, some extras and about 80000 km)?