Don't know if anyone got back to you on this soulshot, but there are actually 2 distinct fields in the items table, the price which is how much to buy the item from a vendor, and the sellrate which is how much the vendor will pay you for them, So you can adjust the sellrate as you see fit, I have a whole long explination about that which is only slightly out of date if you (anyone) needs a tutorial on how to manipulate the price and value of items and creating the merchant id
http://www.eqemulator.net/forums/showthread.php?t=17201
In this case i believe the "merchantprice" in the tutorial would be the "sellrate" in databases today, and the "Cost" in the tutorial would be the "price" in the databases today... but someone more up to speed on the items table may post to correct me on that one, i've been delving more into the spawns area than anything else atm...
Hope that helps.