If I didn't know a lot about bikes, I would buy new from a bike shop. They would hopefully steer you in the right direction.

Older bikes may look good on the outside but it is the inside I worry about. When was the last time the bottom bracket or hubs were overhauled or at least had grease put in them? Are the spokes 20 years old and have oxidized enough to break? I am not say8ing buying an old bike is a bad thing but you need to know what you to look for so that it doesn't become a money pit.

I agree with Tjs...the Cannondale is not an appropriate bike for commuting, there are better choices.