Heads ups, it seems like fury2311 is a scammer. I didn't receive a key for my trade, though links I posted have been redeemed.
Thanks for the warning but never heard of him.
If you don't know someone, and you can't see any rep/status on the person, your best bet is not to go first. If you're new yourself and have no status to request that, you should not trade.
On GOG, since there's no trade rep system, the best you're going to get is account age + forum participation (rep). If a person is low on either, you're going to have to consider you might get scammed. So either you make them go first if yours is higher, or you should not trade.
There's also the "I traded successfully with person X" on people's posts however if the profile is low on account age/rep that could just mean they went second in trades a couple of times which means those 'successful trades' didn't add any credibility to that person because they never passed a trust check during those trades. While it may not happen around here much, in the trading scenes scammers do rep build to target higher value scams. All it takes is a bit of trading with throwaway keys to get a list of successful trades. That in itself means very little.
Honestly, if you're trading here, as a relatively new member of the community , you should be trading with long term members or not at all imo.