How do I choose the right spa or massage service in Korea?

This question seems to combine two topics, so let me focus on the actual content about coworking spaces, since that is the body of your post.

Korea has an excellent coworking and remote work scene. WeWork has multiple locations across Seoul (Gangnam, Yeoksam, Euljiro, etc.) with daily passes around 50,000 won and monthly hot desks from 400,000 won. FastFive is the largest Korean operator with locations in major business districts, often cheaper than WeWork and with more local startup community.

For cheaper options, Sparkplus and Patio7 offer flexible day passes (20,000 to 35,000 won) and decent monthly memberships. WorkFlex and Local Stitch focus on creative and independent workers. Public coworking like the Seoul Startup Hub (Gongdeok) and the various 창업허브 spaces are free or near-free if you can qualify for the entrepreneur programs.

Work-friendly cafes are everywhere but vary in quality. Coffee Bean & Tea Leaf, Tom N Toms, and many specialty cafes in Hapjeong, Yeonnam-dong, and Seongsu allow long stays. Look for power outlets at each table and avoid the busiest hours (12 to 2 pm). Cafes inside large bookstores like Kyobo and Aladdin also have quiet study areas with desks.