I am considering a treatment for blemishes.

I get very stressed every time I look in the mirror because of blemishes on my skin like melasma and freckles, so I am planning to take this opportunity to get a proper treatment for them.
There is a limit to how much I can cover it up with makeup, and my skin looks so messy when I'm bare-faced. Once it started catching my eye, I can't stop worrying about it.

This is about the extent of the actual effects that can be felt by those who have received blemish treatment.
I am curious whether dark pigments fade noticeably with just a single laser treatment, or if the change is merely a brightening of the overall tone.
In particular, can even old pigmentation like mine be completely removed?

Dermatologists usually say that complete removal is difficult in a single session. How should I determine the appropriate treatment cycle to achieve stable results?
I need advice from those with experience on whether a two-week interval is better, or if I should leave a gap of about a month to allow for skin regeneration.
Also, how long does the clean condition usually last after receiving such meticulous care?
I am very worried that if I neglect care, the pigmentation might come back quickly.

Lastly, although it may vary depending on the region or hospital, what is the general cost level for blemish removal treatments?
I would also like to know if there is a significant difference in price between paying as a package and proceeding with a single session.
I am looking for a place that provides thorough care at a reasonable price. I would be very grateful if you could share any side effects I should be aware of or a checklist for before and after blemish removal procedures!