Sorry in advance if I missed something, speed-read this thread. The C230 has my vote in the looks department, but you are going to find it greatly underpowered (although it won't be much different from the Limited Crossfire - absolutely no offense intended).

Assuming you accept that, two huge things I hope this particular C230 has is (1) the bi-xenon package (an expensive upgrade when new, and really a must-have with these older C classes now on the used market based on what you pay for the same model without the bi-xenons), and (2) the wood grain trim, not the chintzy looking aluminum plastic that was in the C55. Although, since the C230 only has the AMG package you may be forced to have the crappy plastic.

Lastly, the price is too high. I am not typically the first person to say this, but based on C55 resale values, they can go lower. The C230, while a good looking car, looks much older than an '07 since that body style was being produced since '03. MB upgrade the rims on the '07 which was nice, but its an older model. And with higher mileage C55s going for the high-teens in terms of price, you can definitely get this one down. People aren't on the dealership lot saying, "Hmm, I wonder if they have any older c-classes". Unless this is a really clean example of the C230 and you think people will be drawn to it when on the lot, you probably have some negotiating room for sure.