1. Get a Wowpass: this is essentially a cash card. Put your foreign currency in the machine and it will convert into Korean won for you. The card comes with 10,000 won of T-money for public transportation. It cost about 1,600 for me to get through 2 subway lines and 1 bus.
2. Buy your AREX ticket in advance and save the QR code. It costs about $7 through a booking app like Klook or Kkday.
3. AirBnB is great if you like having a kitchen and washer/dryer.
4. Groceries are slightly cheaper but I wouldn’t say substantially cheaper.
5. Use Naver Map. Korean addresses are more accurate than English.

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