Not that I would be one to use purchase anything from an unknown person via one of these sites anyway, but deal is over before it began right here:

Speaking to Action News Jax, the woman says they told the stranger they would pick up the dog, but he allegedly insisted on coming to their house to drop off the pooch himself.

Father is beaten and shot dead in front of his children after answering a Facebook ad offering a free puppy

A Florida father-of-two has been beaten and shot to death in front of his fiancée and their two young children after responding to a Facebook ad about a free dog.

Christopher 'Scott' Bowman, 39, was killed on Wednesday night inside his Jacksonville home during a physical altercation with a man who claimed to be giving away a puppy.

Bowman's fiancee, Chelsea Bowman, says their family wanted to get a dog, so they responded to a Facebook post from a man offering one free of charge.

I saw that earlier today on Facebook. It made me sick.

People suck.

EPIC FAIL-
So many things wrong here.
You invited a stranger to your home.
You let them in.
You served the stranger alcohol?

Nothing to die over.

I don't facebook or what not, but do and have done several transactions through Craigslist.

Common sense is your friend, but of course it's not taught in school.