First time getting cosmetic procedures in Seoul, which area is most convenient to stay in?

Hi everyone, I'm Dan from China. I'm currently planning to get some medical aesthetic procedures done in Seoul, but I have no idea about the geography of the city. I've heard that Gangnam and Apgujeong have many beauty clinics, but I don't know where would be most convenient for a tourist to stay. Can anyone share their experiences? For example, about the area you stayed in, how convenient transportation was, and the surrounding environment?

I'm looking for a location that's close to medical aesthetic clinics, has subway or other transportation options, and ideally, places to eat delicious food. However, I don't want to spend too much on accommodation, as I'll already be spending money on the procedures (laughs). Can any of you recommend something? Which areas do you usually choose?

Also, I'd like to ask, if I go alone, how far in advance should I book appointments with clinics? And what should I bring with me? I'm a little nervous, so I hope those with experience can give me some advice!