This module creates coupons with bonuses for the Sponsor and Referral (friend), when they make the registration or orders. There are a lot of configurable options in this module.
https://addons.prestashop.com/en/sea-paid-advertising-affiliation-platforms/19203-referral-and-affiliation-program.html
This module adds an additional tab on product edit page where you can manage your product base and combination prices for each customer group on single page.
https://addons.prestashop.com/it/gestione-prezzi/29289-custom-product-price-for-specific-customer-groups.html
Allow your customers to register and login the store using their username. Customers can create username of their choice or they can select one from the suggestions shown to them on the basis of their first name, last name & date of birth...