sorry for my 99 questions but i have more..
lets say i start a digital goods selling topic.
how the escrow could verify microsoft key/steam/amazon or anything like that
i know there is few ways to verify some of those without being used, but some cannot be verified/check
and what stop the buyer if the keys cannot be verified by the escrow to say they were already used or invalid?
Dealing with annoying people is the cost of doing business. Don't send first if you don't trust the other party, or deal with the fact that some users (mostly newbies) are going to try to scam you. After some time of being a legit seller non-rule breaking negative comments from trolls and competition will matter less.