Restricting access to Conversations?

  • As our forum evolves, we have found it necessary to restrict non-paying members from the conversation system because they are using it to circumvent our rules on sales and other things.

    However, then the staff and moderators will have no way to contact these users other than email.

    Are there any suggestions for how Conversations can be implemented between Moderators and non-paying members, without giving them (non-paying users) the capability to also send and receive messages to & from other users?

    Or any other way for staff to contact non-paying members, and vice versa, other than email?