Community prompt: What first-week setup step was hardest in Jeju?

Experience

This is a Settly Team starter question for the Jeju community, not a user-submitted story. If you have handled phone numbers, bank accounts, transport cards, local apps, identity checks, and address text in Jeju, share the detail another foreigner would need. Helpful answers include neighborhood or station, visa or stay type, timing, approximate cost, documents, place or office visited, what blocked you, and what finally worked. Do not include passport numbers, residence numbers, bank details, reservation codes, exact room numbers, or private contact details. For visa, tax, medical, or legal decisions, check official sources before acting.