First time getting treatments in Korea, how should I plan my itinerary and budget?

Hi everyone, I'm from Taiwan and I'm considering getting a treatment in Korea. Honestly, I'm a bit nervous about how to plan it cost-effectively. I've looked into flights and accommodation, and just the round-trip airfare plus a few nights in a guesthouse or a small hotel adds up quite a bit. Add the treatment cost itself, and the entire trip's budget becomes a bit unpredictable.

I wanted to ask, how many days is generally reasonable to stay for a treatment? Can I get the treatment done and fly back the next day, or do I need to stay longer for skin recovery? I'm a little worried about potential complications requiring a follow-up visit, and whether it would be troublesome being back in Taiwan. Also, does anyone have an idea of the general budget needed for the entire trip (including flights, accommodation, and treatment) to avoid any major surprises? I really have no clue and I'm afraid of underestimating or overestimating.

If any of you have similar experiences, could you share how you planned your trip? Especially how you balanced budget and results. Thank you all!