Need help Sorting and Subtotals formultiple ranges with varying rows in a single worksheet

[astroman72]

Hello everyone,

I have a worksheet with the company's A/R. I am new in the world of macros but by trial and error and with what I have learned from reading on this forum I managed to write a macro that organizes the original data by grouping the "Past Due" and future due dates by week. The Report is almost at 75% of how I want to see it.

What I am missing and need help with is a macro to do the following:
1. Sort in ascending order (just columns 1 thru 12) in each range of A/R Invoices by Customer Name or (Column "C").
2. After sorting, separate the DIFFERENT Customer Names with a blank row.
3. For those customers Names that have more than one invoice, add another row with their Sub-totals
4. In column 13 (Total), last row of each range, Sum up single Invoices and Sub-totals for a GranTotal for each Group or week.
5. Each group should be separated by two empty rows after the Grand total row.

The number of rows for each group will vary every week, depending on the volume of new Invoices, the ones that become Past Due and/or those that will become due in the weeks to come as well as those that are paid but the number of columns will always be fixed at 16.

I have attached the original worksheet before and after running and the Macro I wrote for information.

Your help will be greatly appreciated.