Welcome, Debra, and I’m glad the info has been helpful!
It’s hard to kill a hair on the first shot. The “kill ratios” aren’t well-established, since there are so many variables. I probanly had to have most of mine hit a few times, but they were very coarse.
It usually takes six months to a year to get most of the hairs in a limited area like the chin. you’ll have to go more at fisrst to get them as they’re coming in, but after a while, you’ll be able to slow down the number of treatments.
To help with post-treatment redness, avoid the sun, don’t put makeup on the area, and use a soothing product. They’ll often pout a little witch hazel on right after. You can also put on some 100% aloe gel (no menthol or other additives), which can help the redness subside faster.
Once you’ve done the research and chosen someone you trust, it’s a bit of a leap of faith, I know. But you sound like you found someone with lots of experience who’s telling you all the right things. I know it can be a little nerve-wracking to commit a lot of time and money when you’re not 100% sure of when it will end, but with any luck, you’ll be almost done by year’s end and will have forgotten all about it by next summer!