With the addition of the House Vault selling feature there was a major glitch that SOE missed. Here's the rundown of how to do it. Buy an Inn room for 5 silver. Put a box in your vault, put a rare item in the box(Prefereably worth at least 10 gold). Now relinquish ownership of the house but leave the items in your house vault. Go to a new room and buy it in a different part of town. Here's where the glitch takes place. When you set up vendor mode, the items you left in the old house are still available in your inventory, even though you don't have access to them. Now have a second account or a guild mate ready at the broker. List all your item from the old house for sale at 1 copper. Start selling and have your partner search for you at the broker. Once he has the item up just spam the Start/Stop Selling button and have him spam his Buy from Broker button. You can fill the partners inventory up in a matter of minutes with the same item, then sell it back to the merchant near the broker and watch your bank increase. We duped 300 plat in about 30 minutes between 5 of us. Beware though. Because of our greed we were caught when we did it again the next morning. All they noticed on the database was the actions of the morning, not the evening before.