^That. If you can, just get it from eBay or something.
But if you're going to order from Craigslist, MAKE SURE it's a local pickup and you actually use the machine to make sure it works right (including inserting a SIM on the spot) before you pay.
If you don't take precautions, it could be something wrong with it or you end up sending money through Paypal or something and never hear from them.
I recently tried to sell my MB to someone; for some reason he couldn't send payment from his bank through Paypal (I should have just stopped there) but I ended up driving 2 hours down to his town, waiting for 3 hours, and him never showing and completely dropping the deal.
I mean, it sucked, but most of all it was a whole tank of gas. Make sure it's somewhere close to you, in broad daylight, and bring someone if you can.