I have a '95 320 and absolutely love it. So far, knock on wood, my yearly maintenance is only for my oil change. That's amount to $35/year and I have the car since new. I have thought about upgrading to a 600 many times, but changed my mind after reading from various MB forums about the complexity of the vehicle.

Some will tell you the 500 is a better car. Most 500 owners will tell you the gas mileage is not that much difference than the 300/320, but I tend to disagree. Consider the extra weight of the engine + extra power + extra fun = extra gas. But that's just my opinion. With that much more torque, it will be a waste if you don't stomp on the gas a lot more.

Careful inspection of the car is a must. Pay extra attention on the roof mechanism, and water leak on the A pillar. I would recommend once you find your car, take it through a car wash with the soft/hard top on to check for water leakage. Operate the soft top as much as you can, put the hard top on and off a few times. Hopefully, if there are any problems, it will manifest themselves by work it hard. Also look for oil stain around the A pillar and in the trunk. It is a sign that the cyclinders are getting worn.

Another thing you may consider is the seat mechanism. Check to make sure they operate as they should. Some members here had problems but usually an easy fix.

Look for oil stain on the haed gasket for pre-95 vehicles. The 104 engine is known for premature head gasket failure. But usually that should not be a problem as most gaskets should have been replaced by now.

Pre-95 models also have wiring harness problem. Mine has not manifested itself yet, but I know it's just a matter of time. There really is no safe way to check except look carefully for crumpled insulation.

I think the most important piece is the service histroy. Look for one that has full history. Sounds impossible? Not really, they are out there. I keep all my service receipts from day one.

Good luck, the SL is a great car if you find a perfect one. Patience is what you need.

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95 R129
04 Infiniti G35.5 BS
10 X204