unreally unproductive answer 

at least team up with a plug in so that they do the work for you, if you can't do it..

all you have to do  to IS: 

 - select all cash only expenses for the period
 - categorize them in a meaningful way by a custom field (similar to PL , or different) 
 - allow to build a report with date range. 


how difficult is that?  any developer with 1 year experience can do that....  and you as a company with all the resources and programmers can't handle this?