You can easily get there by getting off the plane and taking the Airport Express Line. You can go directly to Money Box Hongdae without transferring at all, reducing the burden of getting your money exchanged.
Money Box Hongdae offers the best exchange rates in Hongdae, and also has a 24-hour automatic money exchange kiosk, so even late at night or on holidays, you can easily exchange money by yourself.
Money Box provides assistance in Chinese, English, Japanese, Korean and other languages. When downloading coupons and using them, you can enjoy the best discount on handling fees.