One email and password for staff, centers, and agents. We open the desk that matches the account.
Same email can be a center, an agent, or both. A center sees every agent who joins with that center ID. An agent sees only the orders that used their agent ID at checkout. Staff accounts are added from the admin desk.
Short is easier to say on the phone. Letters and numbers. Case does not matter.
Customers type the agent ID at checkout. Enter the center ID you belong to — it has to match a center that already exists. The house ID is reserved and cannot be claimed. Center and agent IDs cannot match each other.