You can get more information on visas and passport at the following link: https://english.visitkorea.or.kr/enu/TRV/TV_ENG_2_1.jsp
You can get more information on the climate of Korea at the following link: http://web.kma.go.kr/eng/index.jsp
Korea’s official monetary unit is the won (KRW). When you need to exchange your foreign currency into Korean won, visit a bank, exchange service center, or an authorized exchange. (Bank business hours: 09:00-16:00, closed on Saturdays, Sundays and public holidays.)
Most of the businesses in Korea widely use and accept payment by credit cards, including at major hotels, department stores, large restaurants and stores. Visa, MasterCard, American Express and other credit cards can be used.
Traveler’s checks can be exchanged for cash at banks or exchange booths. A number of stores still accept the checks instead cash. Nonetheless, the forms of credit cards and debit cards have become a more preferred means of payment by travelers. Thus trading checks is hardly observed nowadays as there is seemingly a decreasing number of stores that offer this service.
You can get more information on Korean currency and credit cards at the following link:
Korea’s Tax Free System can largely be divided into “Duty Free” and “Tax Refund.” In Duty Free shops, no tax is applied to the price of the items, including Value Added Tax (VAT) and Individual Consumption Tax. These stores are generally operated by large department store chains located in airports and downtown.
Tax Refund refers to shops that apply a tax to the items and after purchasing at the full price, tourists can apply for a refund of the taxes paid before leaving the country. In general, tax refunds can be received by submitting the receipt at the proper tax refund booth when leaving the country. However, from January 1, 2016, tourists can receive an immediate tax refund below a certain limit when shopping at certified Tax Free stores. Starting at department stores and marts where foreigners typically shop, the immediate tax refund system is expanding to all Tax Free shops. You can get a refund for 10% of your purchasing price. You can get more information on duty free and tax refunds at the following link: https://english.visitkorea.or.kr/enu/SHP/SH_ENG_1_1.jsp