1st dock is free and 5 hours to build, 2nd dock for 500File:Gold.png and 6 hours to build, 3rd dock for 3,000File:Gold.png and 12 hours to build, 4th and last dock for 30,000File:Gold.png and 1 day to build. More docks you have more merchants can trade with your island. When you build and upgrade your docks, you’ll attract looking to buy a wide variety of goods from you. These merchants are ready to trade their Coins, Gems, and other items, but they can only wait around so long. Be sure to help them out as quickly as you can! Tap any Merchant icon to view that merchant’s offer.