We responded to a few RFAs that required modular budgets.  We asked the
PI to complete an old-style itemized budget for internal use so that we
could check salaries and compute indirect costs.  There was some
grumbling about this--"If NIH doesn't need it why do you?"--but not
much, since most PIs computed the modular budget by starting with a
traditional one and rounding upward to the nearest $25,000.  More than a
narrative went into the application, though; as I recall, the
instructions asked for Form Page 5, the five-year budget form.  A
justification accompanied this, and we sent in traditional
justifications, organized into the categories of personnel, consultants,
equipment, etc.   They contained enough detail to show the reader that
the modular amount was reasonable, but many of the costs--e.g. for
animal care--were rounded to the nearest thousand.  Based on the three
or four such applications we processed, I think modular budgets require
more work from sponsored programs offices, not less--but this could be
diminished with experience.

--
Peter J. Dolce, Ph.D., Director
Office of Research Support Services
Meharry Medical College
Nashville, TN  37208
P (615) 327 6703
F (615) 327 6716