Seoul Beauty Trip — Which area is the most convenient? Accommodation recommendations?

Hi everyone! I'm Mengju from Taiwan. I'm planning a beauty trip to Seoul this fall and would like to ask for your advice.

I've heard there are many beauty clinics and skin management shops in Gangnam and Apgujeong, but honestly, I'm not sure which area is most convenient to stay in. Has anyone had treatments at these places? Besides the clinics themselves, what's the surrounding environment like? Is shopping and eating out expensive?

Also, regarding accommodation, does anyone recommend staying near the beauty area, or would it be more cost-effective to stay in other convenient locations? This is my first time going to Seoul alone, so I'm a little nervous (laughs). I'd love to hear any personal experiences or suggestions! Thanks!