Prices go for 100,000won on weekends for 2, suites that can fit 6-8 people can be had for 170k, and something sizable enough to fit 20-30 ppl will run you about 440,000won. Rooms also have kitchenettes and jacuzzis, and balconies overlooking the outdoor pool.
Getting to Pohang, you can probably handle easily yourself, via intercity buses, however, getting to Bada Pension without your own car, might prove tricky. Expect about a 20,000 won taxi ride (one-way) from downtown Pohang. Tell taxi to plot the following into his/her GPS: 경상북도 포항시 북구 청하면 용두리 46-6. They can also contact the pension at 054-243-2277