Craigslist experience

Hi there!

I was wondering if anybody here had ever had to buy a car after finding it on craigslist, and how that worked out for them.

I've never bought a used car before so I have no idea what the correct procedure is, and what kind of documents I would need. I'm talking about proof of ownership and insurance and things like those (I'm in IL btw).

I'd really appreciate it if someone could help me out, thanks!