Thanks Roller.
Here it is:
https://inlandempire.craigslist.org/cto/d/mercedes-benz-320-cdi-turbo/6688536153.html
The carfax was good and clean, it's a Florida car, and the lower miles appear to be true.
The receipts weren't present, they were at the son's work, or something like that. Plus they only go back 4 years, not the entire life of the car like I thought. That SBC unit really looks like it has already been replaced though, and the buddy I had with me concurred on that. The "new tires" are only new on the back only, The battery was dead, and the tags expired last month. I really probably should have walked. One thing in this car's favor is it is super local to me. It sucks going to another state to buy a car that might turn out to be a POS. We had a nice, cordial but frank discussion. I did like I said I was gonna do (here last night), I showed him the money and then told him I had to see under that shroud. He let me. It looked good! The car drove well too! What to do? I gave him $4,800 and drove the car home. AS SOON as I pulled behind my house the "check engine" came on. Good times! And don't forget there is that $750-800 back seat air bag job that has to be done. Aren't used cars off of Craigslist a blast? But at least there was no black death (bringing the thread back on topic).