If the body and interior are in good shape it's always cheaper to repair a car than to buy a new one. To replace your Benz with a new one of the same size would cost you around $800 a month with a healthy downpayment. You can have a heck of a lot of work done for that amount! The problem, as far as I'm concerned occurs when you have a large dollar problem along with rust or interior work.
I just had some rather expensive transmission work done on my '84 380SL and I didn't even think twice about the repair. To me it was $800 (the repair cost) verses $115,000 for a new SL. Some people will say to buy a newer version of what you have but I'm a firm believer in the old "Devil you know" adage. I have a friend that traded in a 450SL that needed a new head gasket and exhaust for an '88 560SL with 50K on it. Two months after he bought it the head gasket went bad...then the A/C compressor....then the tranny sprung a leak necessitating a $1200 repair.
Keep what you've got if the body and interior are okay. At least you know what you're up against!
