Typically for more common items, we like to stick to our price tiers in s-tags, occasionally you will get an item that is less common. When this occurs, you or a manager may want to look the item up and see what items like it are going for. The best method we have found is to use a site like eBay and check to see what the sold prices of the items are. From there, you can take a percentage off of the item, anywhere from 15% to 30% of the items depending on the condition of the item and the rarity of the item.