First time getting cosmetic procedures in Korea, how should I budget and plan my trip? A little nervous

Hi everyone, I'm Peichun from Taiwan. I've been thinking about going to Korea for a treatment recently, but honestly, I have no idea how to plan the entire trip and budget. Just the cost of flights, accommodation, and the treatment itself adds up, and it feels like a significant expense. I'm a bit unsure if I can afford it.

I'd like to ask everyone, how long do treatments typically require for the trip to be worthwhile? I mean, should I fly back immediately after the procedure, or is it better to rest there for a few days? Also, does the overall cost differ much between visiting during the low season versus the peak season? I don't have specific numbers yet as I'm still in the research phase, but I would be very grateful if anyone could share how they generally plan their entire trip.

Additionally, I wanted to ask if anyone has traveled alone? Or is it better to bring a friend or family member along? I'm quite introverted, but I'm worried about potential issues if I go by myself. I hope those with experience can offer some advice. Thank you!