Looked at a '94 R129 SL500 today 85K miles, thought I was going to make a deal. Until I viewed the car and had it inspected. It was a total mess even though it was driveable. Fuses blowing, ABS, ASR lights, soft top wouldn't go up, throwing multiple codes, it was so bad I told the technician doing the inspection to cut it short. Told the seller to take a hike.
Bottom line, don't buy a R129 with an iffy history, and invest in a MB mechanic inspection report, as well as Carfax. While beautiful, fast, and solid, they are NOT like 107's with minimal electronic dependecies.
But I'm sure evberybody knew that.