I've sold a lot of Apple devices on Craigslist (iMacs, MacBooks, iPads, iPhones etc...). When you are dealing with people you have never met, you have to be "Streetwise", especially if you're selling in a big City (I live in Atlanta). However, by following a few precautions, it can be relatively safe!
The keys for me are:
-Place strict stipulations on buyers: you'll only respond to people who provide a phone number, you'll only accept cash, the transaction will take place inside you're local bank (and stick to these rules).
-Doubt means no! Trust your intuition. If you have "any" doubt the buyer is not legit, Stop! You'll learn to spot the potential scams fairly quickly! Never let greed trump common sense!
You might lose some legitimate opportunities by following the above, but you'll weed out many more potential scam artists...and that's the goal! Most potential buyers who are legit will appreciate the effort and realize it makes the process safer for both parties.
It's worked over and over for me!