That looks a very special car but the seller has used one of the best Mercedes cliches...
"This incredible vehicle is often referred to as the last Mercedes to be 'over engineered' a Mercedes trait that was costing the company in product delays and over budgeting."
And "an appriciating (sic) investment" - I love my C124, but none of the three that I've owned have ever shown the slightest sign of increasing in value: perhaps I should reinvest in V12s.