Like the guy above me said, trust is necessary in business. If you are new you will be bound to go first[you won't find MM always] and will suffer high risk of being scammed too.
Newbies should use a trusted member of the community as escrow if they are to trade with other untrusted members of the community. Just because someone is labeled as a newbie does not mean they actually are, nor does it mean they are a scammer, although the chances are very high. The opposite is true as well, just because someone has a senior, or a hero account (or a legendary account) does not mean they will not scam you if they do not have any trust.