How it works...

While there are many steps involved, the process of inviting an existing account is a relatively simple handshake process. This means that both sides must actively initiate/accept the invite, in order for it to succeed—an invite cannot be forced.

After specifying the target account's account ID (or e-mail address), the e-mail address associated will be notified.

As part of the handshake process, the invited account must explicitly accept the invite.

After confirmation, both parties will receive an e-mail detailing the membership. From this point forward, the bill for the invited account will be paid by the master account.