Is this a good price for a 100CSQ?

[Scott 20191668 Bermes <scottb2460@earthlink.net>]

Does anybody know the dealer black book value for your region on a 94
100CSQ sedan with 40k miles?  The dealer has a "non negotiated" price of
$19,900 and according to my credit union, NADA full retail is 23k.  My
guess is that they got the car at the auction or grave a crappy trade in
of $15K-$17K.  

I would still need to sell my current 100CS, but was curious before
putting any serious effort into selling my car. Appreciate any info.

Scott