Thanks for the replies. Most helpful.

I phoned one of the local Mercedes repair shops this afternoon to get an estimate on the replacement of the chain(s) and tensioner for the two models I am likely to purchase. One is a 85' 380SE (if we agree on a delivery fee) and the other is a 84' 500SEL. The lady got all of the info and phoned me back. The results are as follows:

For the 1985 380SE: $226. (tensioner and other parts), + $103. for the chain and + $196. labor. For the 1984 500SEL it is also $226. for the tensioner and other parts) + 112. for the chains and + 196. labor. Both are a little over $500 each. Does this seem reasonable?

There is another local Mercedes shop that I am going to phone tomorrow. I am unsure when the chain was changed on the 85' 380SE (which I am more interested in, because it is cheaper and they are willing to deliver). I talked to the owners daughter and she said she knew for a fact it was changed before, but does not recall the mileage and would ask her father. Not a big deal, because I will buy the car either way and if the miles of change are unknown, I guess I will go ahead and have it changed. Any other parts I should go ahead and have changed while it is apart?

I really like the longer look of the 84' 500SEL and the fact that it has the driver airbag option (which the 85' 380SE lacks), but I would say that an airbag system that old would not be that reliable? For $1500 less, I can live without the airbag I suppose and just depend upon the standard safety built into the 80s S-Class.

There is a LIKE NEW 88' 300E for $3000, with 114K, 1-owner miles here locally, but I really want the S-Class.

Thanks again guys/gals!