Vintage Cars: 1983 Mercedes 380SL Coupe Roadster, god idea, survival rates

Question
I can get Nada's used car values on this vehicle but cant find anything on KBB, Edmunds etc.  Any suggestions?

Answer
It is tough to find values for most cars of the early 80's, but this one might be an exception.  I'd keep an eye on sites like eBay or any other online site that shows current selling values.  The SL has one of the highest "survival" rates of any car from that era, and they frequently change hands.  Tracking just the ones that sell on eBay alone should give you a pretty god idea what the car is currently worth.