Each independent user can join any group. To join a particular group user needs an invitation. Invitation can be obtained from a group leader who has unused invitations and willing to invite a user into his (or her) group. The way of getting the invitation is not specified anyway and completely depends on group leader's and willing to join member's communication. For example, it can be sent by email. Upon obtaining an invitation a user can enter it into 'Join the group. Invitation' field on 'Group' page and press 'Join the group' on which user immediately joins the group. On joining group all funds available to user are not touched and reside on user's balance but from now on all newly done pictures are billed to the account of the group leader.
Pay them less than $1 for a thousand correctly typed pictures ,

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