I have been looking for a sunday driver, fun car, but am only 20 years old, so I don't have too much money too spend. I found two beautiful cars on a farm in my town, the first is:

a 1980 BMW 6-series (the 635 or 633 badges have been removed) Manual, 85k miles, black on blue (yuck). Has a broken Radiator, and very few rust spots.

the second is a 1984 Mercedes 500 SEC with only 64K miles! Gold on tan (eek), not a spot of rust, cables that connect to spark plugs are disconnected (anyone know why?)

Both cars were driven to their resting spots, and have only been out in the snow for one year. He wants to get rid of both at the sametime, so I'm wondering which I should take? Which one would be less expensive to maintain?

The bmw is a wonderful machine, as they are the finer sports car. One ride in one is like living a dream.
On the other hand, the mercedes is the unstoppable, reliable German luxury yacht.
In my opinion, either car is wonderful. I would see which one runs the best and that you can fix the most easily and cheaply. Then, I would take that one.

Personally, I'd stick to the MB. Especially if you can learn to do maintenace on them yourself.

Dig around on www.benzworld.org and on www.mercedesshop.com and you'll find an amazing amount of common sense maintenance specific to the MB models.

From the cost to maintain perspective, every time I've compared the MB and BMW parts, the MB stuff seems to be cheaper, at least as long as you're staying away from the dealership parts department!

(I'm buying my second MB today, ironicly enough, it's a 500SEC as well!)