This is such a great sticky. Thoroughly helped me to make an informed decision buying my 2007. I wanted to add a couple of bits of small advice, that I've only noticed since driving it for a while.

1- Engage parking brake and check that it holds on a hill.
This is a pain of a job to potentially fixed and easily missed when you are busy inspecting for bigger issues

2- Sunroof rust around the edge. Open the sunroof and inspect- simple really. If rusty check for blocked drainage holes or use to negotiate a price reduction depending on levels of rust. ( This can also go for trunk window )

3- Drive for a while- I know this sounds silly. But bare with me. I am 6"2 and I have found the driver's seat to become increasingly painful. (I do have a bad back) but this is the only seat to aggravate it. I believe there are some other comments and threads about this issue.