Is there a way to generate custom reports on Zoho Invoice?  Because I use a cash accounting system, the current reports do not display all the information in the way that I need it.

Currently, the sales report shows sales based on Invoice date, but I only want to record a sale once the payment is received.

Also, I separate my income by categories (coaching sales, apparrel sales).  Is there a way to create a sales report that will separate into categories, not just by item ?  With sales by item, I have to manually add the the values for each item into it's category (either apparel or coaching, etc).

Finally, the overdue invoice report shows only the total amount of the invoice, not the past due amount of the invoice.  I realize that the aging report shows the actual value past due...maybe i'm not knowledgeable enough about accounting to apprecitae the differences.

In any case, if there is a way to custom write reports, I'm comfortable with SQL as long as I can see the DB structure. 

So can all this be done in invoice?