How many sessions of Liviheal do I need to get the full effect?

I'm hesitant because there are a lot of posts saying that one application of Libby Hill doesn't make a big difference.
I'm curious how many Libby Heal sessions you usually need to feel your skin has improved.
I'm interested because I heard that consistent use of Libby Heal dramatically changes your skin texture, but I can't ignore the cost.
It would be helpful if those who saw results could let me know from which session they started seeing changes.