Thanks for the comments and advice, all.
Regardless of the Boxster I move forward with, I'm certainly going to get a full PPI w/ leakdown and compression tests. And I'm going to have the clutch and IMSB done when I buy; 75k isn't a bad time for a clutch change, and for the incremental ~$800 I'm not going to gamble on the original IMSB, particularly when I'm going to drive the car ~2,500 miles in five days soon after purchase.
The car in question was a CA car for nearly its entire life (65k out of 75k), and it wasn't driven in the winter up here in Illinois since moving here, so there shouldn't be an issue with corrosion or other northern driving issues.
Re: traffic, I'm going to live pretty close to my office for the first few months (as in, biking distance), while I look at traffic patterns and prepare to buy a house. Good thought, though...I've been there: It once took me 1:40 to SFO from my company's office in San Ramon. It was not fun.
I test drive the car tomorrow. I should have a pretty strong negotiating position as no one in Chicago will think about buying a convertible until spring.
