suggestions of hotels are in the link below. You can contact hotels directly
http://www.lottecityhotel.co.kr/ http://www.koreanahotel.com/ Charge
for one room per night is in the range of 140,000 Korean Won.
http://www.casaville.co.kr/ (Click 'Shinchon, Seoul' at the main page) Charge for one room per night is in the range of 77,000 Korean Won.