Word of caution: do NOT pre-pay for your sessions because my laser center in La Jolla, CA went out of business around 2004 (dont remember exactly when) without notifying anyone and skipped town with our money! Ask if you can get the same discount if you pay for 1 other session in advance & explain why you are asking due to bad experiences like above.
Otherwise it was one of the best things I've ever done because I hate shaving & never have to again in my bikini area my entire life (except a bit of touch up on few stray hairs left a few times per year.) Expect that it can take quite a few treatments (~8-10!) to get most of the hair & you may need occassional touch ups every few years in the future - everyone is different.
I had ~10 treatments done 5 years ago & 99% is gone & has stayed gone; remaining 1% grows very slowly & I just shave/pluck those few left a few times a year. If you do not have very noticeable results after the 3rd treatment then I would go to a different place as it should be very noticeable by then unless there is an issue with your particular body situation (which can happen.)
Also realize that you'll never have 100% of the hair gone as there are always a few resistive strays but 99% of my hair is gone in the area I did. I feel cleaner & less conscientious when I'm in locker rooms & hotels because I am totally bald down there now - look like a little girl vs hairy which I think looks much better. Some people may feel less sexy without it though - it's very personal.