Depending on requirements, there are some decent accommodations available from airbnb that are easily 30-40% off the price of hotel of similar size, plus kitchen and washer / dryer facilities.
If staying in hotel is a main requirement, can consider Savoy Hotel at Myeongdong. The room is cozy and the size is spacious.
Another one which I looked up before is Nine Tree Hotel, also at Myeongdong. It is new and looked very nice from the photos. Not that pricey too.