[ QUOTE ]
...Mr. Angry Craigslist will get his ass kicked, most likely.
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Not even worth messing with. That posting is the sign of a mentally unstable individual that you don't want to antagonize, whether or not you can kick his ass.
A similar situation locally a couple of years back ended with the guy who got sniped on a car showing up at the buyer's house in the middle of the night with a gun. If someone like that shows up on my doorstep, I'm locking the front door, locking the kids in their rooms, loading my gun, and calling the cops.