I had my underarms done in an office, but then bought a device on Amazon and have finished off the pits and did bikini and legs myself. It takes a little longer than in the office but results are comparable. Office visits are every 6 weeks and doing it at home is one treatment per week. Faster, cheaper in the long run and just as effective.
So this is just my experience but I've been using this for almost the past year pretty much wherever I can reach on my body. IPL is a step or two below true laser hair removal but it is a similar principal - intense flash of light meant to heat up the follicle to the point where it shuts it down.
I would say that my body hair has been reduced by a good 75%. This includes legs, arms, chest, pits, and groin. I still have to shave but shaving is alot easier and lasts longer now. And the hair that does still come back grows slower and is finer.
I have tried it on my face and it has been a mixed bag. There are spots that have taken to it kinda well like towards the back of my jaw / ear-line but the bulk of it still remains. Not to much it hurts like @%#@!@$ when used on my face. The pain on the rest of the body is tolerable depending on how well you deal with pain.
The IPL handhelds seem to work best on 1) fair skin, 2) with dark hair, 3) where the roots aren't too deep. The hairs on my face have roots that go much deeper than my body hair so they're still going to require laser / electrolysis.
One thing to keep in mind is that light or blond hairs will likely not be affected at all because there's not enough melanin in them to absorb the heat from the light. If you have darker skin, it likely won't work either and might be more painful to use.
I intend to eventually get laser for my face and maybe elsewhere but for now this has at least helped me feel not as dysphoric about my body hair.
Good luck!