From the Super Mario Wiki
The Keelhaul Galleria is an Item Shop located in Keelhaul Key in the game Paper Mario: The Thousand-Year Door. It is owned and operated by Thriff T., the brother of Plenn T.. The store is first found during the events of the fifth chapter.
Prior to the fifth chapter, Thriff T. tells Mario how he wishes to some day own his own shop, despite how he enjoys working with his brother in Rogueport. When Flavio assembles a crew of people on his ship for the voyage to Keelhaul Key, Thriff T. boards the ship, hoping to be able to open up his own shop when they reach their destination.
When the ship wrecks on its way to Keelhaul Key, Thriff T. takes advantage of this disaster. Once on Keelhaul Key, Thriff T. builds his own shop mostly from flotsam from the ship wreck. The shop, when finished, utilizes one of the ship's sails as its roof, and various pieces from the ship to hold it up. The shop contains six items for sale, half of which cost less than ten coins.
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