That depends.
When you subscribe a client to a plan, they receive access for 3 users on the account, alongside you, at no extra cost. If the client adds users within this limit, they can freely add new ones.
For any additional users beyond the first three, there is a charge of $10 per user per month. If the client attempts to add more than 3 users, they’ll receive a notification instructing them to contact you for further assistance.