Variable buy/sell prices for Merchants?

[Dagmar]

While practing JC I began to notice that the platinum bar merchant in Felwithe began to give me less and less for my sell backs on Platinum Malachite rings, I first noticed at 100pp, then 99pp. To test I sold to another merchant nearby and recieved 103pp. Additionally, the price of platinum bars themselves went up (from around 100pp to 110pp). During this time, neither my charisma or faction changed.

What gives?

[Liwsa]

The more of a certain item a vendor buys the lower his price goes. Like any good traders supply > demand price goes down. Demand > supply price goes up. Of course it takes a lot of an item in EQ to move a vendors price not just one or two. You have to remember you are not the only person selling to that vendor as with most Gem vendors more then one person is doing or did their skill trades at that vendor so they tend to get a lot of buy back items.