Make sure it hasn't been in any accidents, get a Pre-Purchase Inspection, carefully look at all records and service history, listen for any noises or squeaks, and make sure you tuck it in at night.

Maintenance isn't all that bad, most can be DIY if you have the tools but yes, parts are expensive and when they fail they it can add up. I have 150k miles and she's still running strong with no major problems. The car is stout, agile, and fun...just wish it was lighter.