There are many scammers. It is quite easy to figure out when someone is trying to scam. If a seller will not setup a deal in a manner where "both" parties are protected, then usually it is a scam.
Yeah, most times. But buyers are also sneaky. One buyer recently wanted to escrow with a site that said (and this is verbatum) "The arbitrators below were not vetted by Bitrated." So you want me to send my coins to who? Some random who could very well be yourself?
The system as it is, is clearly not working.
There are plenty of reputable escrows. There was also a trust warning of -6 on OP's account. There was also a reluctance to prove they physically own the devices or that they allow the buyer to use an escrow.
The buyer appears to have used PayPal so in the event that this kid likes to waste everyone's time for some jail visits, he will be the one "scammed".