Don't be shy, better out than in ! I'll start, the worst Benz that I ever bought was a w126 500SEL F reg that I foolishly bought unseen from a retired policeman off eBay. The car had only done about 135k miles and only lasted 5 months before the alternator, radiator, condensor, exhaust, battery, bonnet release catches.....all gave up. Oh and just for good luck water entered the boot and gathered where the spare tyre lived. What a day that was when I scrapped the thing and my wife threatened to kill me.....