As far as I know the 2006 C230's have major balance shaft issues so avoid those, 2007's usually don't have that problem but there's a possibility. If he wants a C230, look for a 2007 or anything 2005 and below. If he is ok with any other W203, look at C240's, C320's, but don't look for C280's. I've heard also that the W203's with the 5-speed auto, anything 2005 and below I think have a transmission seal problem or something, also the 7-speed autos have a few problems I think, i'm not the most experienced in the field so look and post in the W203 thread, as you are in the wrong thread.My son is looking at an MY 07 c230. I don't know anything about these cars. I own a MY 95 SL500 and know about it's problems. What should he look for?