personaly, i would tell u to find a person u trust, its not easy but not everyone is bad.
im currently playing with 3 friends, and we trade with each other to avoid those problems.
personaly i dont like the AH idea, makes no sense in the pokemon universe to me, people overprice in AH anyway, how can u not overprice? u cant control that, u can set like, level 50 pokemon cant be more expensive than 50k for example, but it as alot of flaws, 50 Shiny or 50 Normal, u cant make the same price limit for it.
Basicaly it would give alot of work for the developers to set it up and work at 100%
This is just my opinion, feel free to go agaisnt it ;)