An auction house is going to do more harm then good.
If you implement one we're going to run into all those same problems as we hand in FFXI.
I for one do not want to have to wait until getting a craft near max before I can make any money off it. That's going to happend if you implement something with a sales history.
What you need to do is inject some life into commerce.
You can do this with a retainer search.
Once people have a way of expressing what they desire (by having retainers search for items for them), Items will start moving and the economy will finially be born.
Auction house comes at too great a risk, if anything and it's the actual market ward system (the crashes and such) that are causing you to reconsider have it all automated. Have like an auction house interface, but through this you can buy and sell off retainers.
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