1.Do We need to buy a new code for every user that we add in? (Example : If I want to add 10 users, do I need 10 codes?)

2.I want to whitelabel Your tool. For Every new client that I get, Do I need to pay for more codes based on how many users they will add?
(Example : I have 5 clients, they need 5 users each. do I need to buy 25 codes or just 5 codes that can be "re-used" for every new client that uses my tool)?