You should start to see results in about ten days as the hair follicles begin to fall out.
It's a big step to opt for laser treatments when you have a full head of hair. One important aspect of lasers is that the hair does not fall out in a uniform fashion. You might find that after only one treatment, you have passed "the point of no return" if your hair falls out in patches. After several laser sessions, your scalp will have a more uniform appearance.
I have done laser treatments, so feel free to PM me with any questions.