How long does the effect of laser hair removal usually last?

Now that it's summer, trying to groom myself with a razor or self-waxing every day is such a hassle, and I feel like my skin is getting damaged.
The hair in my armpits and philtrum tends to grow a bit thick, so it seems like some discoloration occurs there as well.
I want to keep things looking neat and tidy, so I'm considering getting laser hair removal. For those of you who have tried it, how satisfied are you?
I am curious how long the effects of laser hair removal last.
I looked it up online and saw conflicting claims—some say it's permanent, others say the hair grows back thinner after a few years—so I'm curious to hear some real reviews. I'd like to know if you experienced any side effects like folliculitis or skin troubles after the laser hair removal treatment, and also how often you should get it done for the most effective results.