What's a good price for 1992 100CSQuattro?

[Doug Rudoff <drudoff@homer.spry.com>]

I just looked at a pretty clean 1992 100CSQuattro with 49,000 miles, with
automatic and the Bose Audio system. I've looked at the prices at Autosite
(http://www.autosite.com) and Edmunds
(//http://www.enews.com/magazines/edmunds/index.html) and they differ by a
lot: 

             Wholesale     Retail
Edmunds       $18,150       $21,150
Autosite      $15,650       $18,300

They're asking $18,000 for the car I looked at.

According to Edmunds, $18,000 is a great price. According to Autosite, 
it's not. Any suggestions on what is a good price?

Thanks.

Doug Rudoff                                                drudoff@spry.com