I have a content type EVENT with the event date field,
I created products with various attributes (ENTIRE - UNDER - FEMALE, etc ..)
Each attribute generates a different price for the product.
Product1 -> ENTIRE = € 10 - Product1 -> UNDER € 8 Product2 -> ENTIRE = € 15 - Product2 -> UNDER € 5
Now, in registration (COMMERCE REGISTRATION) checkout, insert the birth date of a user. I must compare birth date with event date. If the user is a minor pays UNDER, otherwise ENTIRE.