Evan alert, Evan alert...
All of his cars are 99.9% rust free. Is that enough?
its amazing how the pictures stop short of the potentially bad areas. he tells you about the floor as that would stand out to the uninformed. one of the rockers looks bad - so what about the a or c pillar, or the back of the firewall ... or the front of the firewall and the interior of the fenders. you got it - NADAGorgeous looking CSi, in my favourite config - Euro spec, Chamonix, manual 'box and Alpina's.
If the ad is correct and 'floor area' rust constitutes only 1% of the entire body, it shouldn't be too bad....should it?;-)
Here's a comparable car that's ~$20k more:
http://www.hemmings.com/classifieds/dealer/bmw/3.0csi/1605824.html
which may be worth it w/o having to deal w/all the hidden rust.