I see this way too often, new members join and automatically think someone with 300+ rep and 3 vouches means they're trusted so it's fine to go first - you can't be more wrong.
I can name 3 people off the top of my head who had a high amount of rep and time on the site just to turn around and throw it all away for a virtual item no one will care about in 3 years; Apostle, Rarity, and now Doctor.
How to not get scammed:
1. It does not matter who it is, always use a middleman because ANYONE is capable of scamming, i can't stress this enough!
2. If a sick tag like "Shadow" were being sold for 20$, it's obviously too good to be true. It will probably be taken back, just like how Afro does that with W ork. He sells it for 20$, calls in it and gets it back 2 days later.
3. ALWAYS make them show proof whether it be photo proof, or a friend request proof, it can't hurt to ask, and chances are if they won't show proof they don't own the tag.
4. If you are selling something and they insist on you going first, and when you ask to use a middleman, they say "we don't need one i'm trusted". You should not go first, just call the deal off, it would be better to have a item with no money, then no item and no money.
5. There are always going to be impostors. If you haven't noticed Philly (the admin/owner) only does deals inside of PM, not AIM. But as always he has imposters. His aim is XBLPhilly, but people pretend to be him on fake aims such as XBL.Philly and Philly.FK. When doing a deal you should always make the other person send you a PM from their FK account. If they can't complete that request, don't deal with them.
Hopefully this cuts down on the scamming, as i am sick of seeing members get scammed and the community go to shit. I will add more when i think of stuff to add. Stay safe everyone