When you make a hotel reservation, you often need to give a credit card number. This will secure your reservation, meaning the hotel will be able to charge you a cancellation fee if you don’t show. When you reserve your room, the hotel does not charge your card.
Check In and Check Out
When you check in, the hotel will ask for a credit card to guarantee extra charges, known as incidentals, but it will not run a charge. You can use a different card than the one you used to make your reservation and a different one than you plan to use when you check out. When you check out, the hotel charges your credit card, whether you visit the front desk or not. Check your bill closely before you leave to make sure you aren't charged incorrectly.
Currency
When you make a payment, the hotel will charge with local currency which is Korean Won (KRW)
** It can be changeable