I havnt done it yet, but from what I understand its generaly 6 sessions... if your going to go with lazer, make sure the place uses a new type lazer like the aurora... the new types have better and longer lasting results... and supposedly work on darker skins, and grey, nonpigmented, light, and red hairs which the older type lazers didnt....
the place Im giong with is a national chain... they only charge you for the 6 initian treatments for a full clearing... for the 2 years following the 6th treatment, you can go back at any time for additional treatments at no additonal cost... but most likely youd end up haveing to finish up with electro reguardless *Shrugs*