Echo1 - no need to apologize as I wanted to help you make a decision based on more data points rather than solely relying on the Google keyword tool. As for your question about whether to use broad or exact match numbers I would always err on the side of caution and choose exact match. If you want to be even more pessimistic in your numbers then divide it by half.
In any case, you should still gather competition numbers by performing an intitle:"keyword phrase" and inanchor:"keyword phrase" search in Google (including the quotes as it denotes exact match). This will tell you approximately how many websites are optimizing their title and anchor text with exact match phrases. Those numbers should guide you toward the right keyword choice.
Lastly, try experimenting with the title tag and vary up your anchor text so you don't "lose out" on the "limo service Chicago" keyword. I looked at the results for that keyword and in the organic listings, no one optimized for it until the website ranked #7.
