You don't need to be a certain age to get Botox. Many people associate wrinkles and fine lines with old age but younger people in their 20s-30s can still get Botox.
Botox cost isn't overly high to begin with, so if you're seeing it for an incredibly cheap price, be sure to question why this is for your safety.
It is important to know that facial muscles weaken over time, and getting too many injections in certain areas can have unwanted results.