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http://www.bookingcenter.com/interfaces-and-modules/guest-services/
As of this writing, there There is no way to set a default 'credit limit' for an individual or a Group booking. Thus, the front desk is required to know if interface support is allowed or not allowed per individual booking. If the guest is allowed to accept automated postings (POS charges, movies, phone calls, etc) then there is nothing further that needs be done, all works automatically by 'checking the guest in'. If the guest is NOT allowed to use the services, then on the Booking Data screen, look for the link called 'COMTROL':
This takes you to a drop-down where you see:
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