Botox cost depends on several factors
Some Botox providers price their product by area treated, others by volume, others by units. The most reliable method is by units. Ask your provider "how many units are you placing in each of the specific areas". The average price for Botox in the Houston area is $14-15/unit. Most providers nowadays will offer specials. In addition, Botox has a "rewards" program that gives you $25 off each treatment done within 3-6 mos of the last treatment, as long as it's done.
