Teleport to house tabs are worth coins, and are generally in high demand, as they're one of the most versatile teleportation items. The tablets are made on mahogany eagle lectern in a player-owned house study. This does not have to be your house. Using a ring of duelling to bank at Castle Wars, and using the house teleport spell to access your house quickly, you can create an inventory of 26 house teleport tablets per trip (two inventory slots are used for the earth and law runes). An alternative to banking is simply using a servant.