----------------------------Original message----------------------------
Vendor service charges are not always as straightforward as they might seem
on the surface.  One good example of this phenomena is the question at hand.
At least one major U.S. vendor supplies information on invoices that leads
the customer to believe that no service charge is being assessed on that
title due to a discount on that title.  However, a careful reading of the
vendor's catalog seems to indicate that these no/low service charge titles
are factored in when determining the library's _overall_ service charge rate.
 By this I mean:  your service charge is determined through some calculation
of title by title service charges, some titles receiving no service charge
(and being so indicated on the invoice) while others receive a very high
service charge (with no indication on the invoice).  The best solution to
this seems to be to choose the option where each title's service charge is
individually indicated on the invoice.  This is my interpretation of
the situation.  Can anyone out there confirm or refute this??

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