Need A few Questions answered

I posted earlier about the right age to remove hair. What I am worried about is that I do not have very much hair on my back at all right now. If I go to remove that hair could laser trigger more hair to become active? The tech who would be performing the procedure for me also said it would be alright to wax after my session! I have heard this not to be true! Any advice would be awesome I am going in to have the procedure done in 2 weeks any advice about pre and post care would be greatly appreciated! thanks