People use trading to scam presents out from others. They try to remove their stuff right before the other clicks on accept, so when the trade will accepted, they offer nothing, but get the others stuff.

It would be great if the trading form would have a timer (2-3 sec), what starts when anything changes on the form, and the users would not be able to accept the trade until the timer goes down.
Also it would help, if the other's trading field would blink or be marked with red for a short time when they remove their stuffs.

Definitely. +1

I know a trading way to circumvent scammers from a website I used.
What it basically was is that both sides can accept or decline and if they both accept, the trade proceeds, and if both decline, the trade gets halted.
Once they both accepted though, both sides will have to click accept again to see if the trade is what was offered and if anything was moved, the trade resets.
Perhaps this could be done the same way with real time?