One of the only marketplace forums I visit nowadays.

Sythe encourages a lot of escrow type stuff.

On Sythe, I once had to conduct a transaction through playerauctions.com, which is an escrow service.

But yes, you're right in that the most secure way is to have an escrow service. The problem is that people don't like to have their payments held for X days if the other guy just decides to not say anything. In addition there are escrow fees, although on Sythe these fees are split between buyer and seller in most cases.

What a lot of people on Sythe do is have the buyer send payment, then open a dispute, then close it. This way, the buyer cannot open a dispute again and try to get the money back.