Choose weather to use the custom pricing on quantity or product

[Valentina R]

User needs to only set the discount to the first person.

Example: product price is 100€.

If quantity is 2, then 10% discount should be 100 + ( 100 - 10%) = 190€

Requested here: https://bizzthemes.com/forums/topic/appointable-product-add-ons-tab-how-to-configure-add-ons-to-not-conflict/