Laundry during a two-week recovery stay — what's the plan?

Packing light because I'll have a compression garment and loose button-up tops, but two weeks is two weeks. Do most hotels in Gangnam have guest laundry, or do people use the coin laundromats? Not sure I'll want to be carrying a bag of washing down the street in week one. Small thing, just one of those details I haven't seen anyone mention.