The 3-6 payments can be from both AR and service invoices if you have the service module, whereas the 3-1-2-78 is only for AR invoices or from jobs. Plus, the 3-1-2 depends on whether you are filtering by a period. If so, you will only get paid invoices from that period. 3-6 shows ALL payments with no filter. You can get a matching number if you change the Period to Between and then put in the year you want.

2-4-31 GL report landscape (so it includes the job info); export to excel, sort by job, add the client as a column, group and sub-total by client.  Seems like an odd thing for the CPA to ask for, income is income, doesn't matter who it came from.

We have the same request.  Makes sense as it is a disclosure in the financial statements.  We run the 6-1-4-61 by the client/job with the periods for the entire year.  We dump to Excel and minimize all the jobs down to each client.  (We have multiple jobs per client and run primarily contracts, not time and materials).  Then we run a conditional formatting for sales over $xx.xx to back into our largest client(s) revenue for the year.  Conversely, in the past we have run 3-1-2-41 and then manipulated through Excel as explained above.

Our CPA asks for the same.  On audited financial statements one of the requirements is to list sales volumne by customer for customer concentration risk.