In my experience with breast hair, your longest appointment would be the first one. The second appointment, which should be done in 3 to 6 weeks, would be shorter, and from there on, you would be going in once every 6 to 12 weeks.
Even at a slow rate of work, a fully functioning professional would spend only half an hour to an hour on your first clearance, and all subsequent work would be 15 to 30 minutes.
In the real world, this would mean that a professional could be finished with this treatment area in 7 treatments, spread out over 12 months. You would pay about $50 for the first treatment, but no more than $100, and the 6 other treatments would cost you between $30 to $60, and be spaced out roughly every two months. This would work out to as much as $100 for the first treatment, but $180 - $360 total for the balance of the year, paid once every two months in installments.
Now, let’s look at the professional side of this equation. When I have done breast work, typically, after the second treatment, there is not more than 15 minutes worth of work, so we are down to what ever the mandatory minimum treatment time costs. Although some businesses charge more for shorter appointments, most just charge a minimum like $20, so we must recalculate this to $50 to $100 for the first treatment, and 6 treatments paid the balance of the year with an average cost of $20, for a total of 120 paid out in 6 installments over the balance of the year. That means that for $220 or less, you could spend the rest of your life with no breast hair. If she uses thermolysis for the entire job, then all 7 treatments could average about $20, and in that case the entire job would be $140 paid out in 12 months, and if the breast hair surrenders early, even less money, as you don’t even require treatment every 8 weeks. There is a possibility on this body part that you would be done in 5 treatments spread out over the year. In that case, recalculate to $100 paid in 12 months.
I think many women spend more on their manicures over the course of the year.