So let's say you're scamming someone from markee or something.
Everything goes good, you show him a fake armory, etc, until he says something along the lines of
"So .. can I see in game?"
Tell him you'd rather not have to do anything with the game and trading. Say a bunch of BS like Blizzard GM's moniter the starting zones, and
"wouldn't it be suspicious if i just made a new character on a random server just to inspect your gear?"
Of course he'll feel paranoid. Just tell him you have a better way of proving that you have the guy.
Here's what you'll need:
Mozilla Firefox Kaizou (Addon) Working WoW Account
Anyways, just tell him you'll send him a screenshot and you want him to do the same. Tell him you'll send the SC first so he knows what kind of picture to take.
Go to the "Paid Character Transfer" page and move one of your characters thats over level 10 (obviously).
Step 1: Kaizou the page. 
Step 2: Change your info. Leave account name the same. 
Step 3: Send him the SC. That's pretty much it, and if he doesn't believe you then just say the trades off then. This has worked flawless for me, 100% times so far. If you don't know where to get kaizou, search it on google. If you don't know how to use kaizou, search around the forums, there's a thread about it. 
