Trade Logs, they will save everyone and it can catch not only Scammers but also Hackers too (SO LONG AS YOU DON'T HAVE THE OPTION TO CLEAR THE FLIPPING TRADE LOG.) But having a trade log means that we can see all the trades we have done and what items were traded and received. It's also a way to get proof that someone traded you a certain item for items that are a lot rarer than theirs.