I have noticed that the C230's are less on Kelly Bluebook than a lot of other cars in its range including the BMW. However, I also know that KBB is a good tool but not great tool. Does anyone know whether the C230 normally goes right around bluebook or closer to tradein?

Also, if anyone has auction values, can someone please look up a 2006 C230? Mileage and options aren't critical...I just want a rough ballpark of how much these are going for since I was thinking around $18,000 here in Seattle for low miles.

 

You might go to several websites and do a kind of "average" from all of them to get a more accurate idea. Or maybe you have done this already. Don't know. Anyway, try:

www.kbb.com (which you have)
www.edmunds.com
www.caranddriver.com
www.cars.com
www.autotrader.com

Some of these show existing cars for sale and what they are asking/selling for.
That's the way I do it when I look at them. Hope this helps answer your question.