I have been looking around and it looks like low 20s is the right price.
The market for big V-8s is really bad right now. Some private parties are selling at low retail value. around 21,000-23,000. Dealers are rediculous asking 27-30.
Recently a black 2000 with 58 k sold for $19k. Some people are lucky and get waht they want out of their cars, most don't.
These cars are going to depreciate for another 5 years or so. Usually hitting thier lowest value at 10-13 years then bouncing back up.
Case in point 500Es and SEC's look at the late 80s SLs damn they went up in price. Its a good time right now to buy a early model AMG.