Hi Abu, before I spend weeks trying to put this together I wonder if its even possible?

I need to create an invoice page using nested master detail. In master I would have clients, selecting a client would load invoices of that client into list1, clicking on the invoice in list1 would load records with that invoice ID into list2. This would allow me to add multiple entries to an invoiceid in list1 from list2.

As I understand all detail grids are linked on the id from master grid, I need list2 to link to the invoice ID in list1. Changing your demo to allow add on list2 does not insert any data;

Example;

Master record ID 10
List1 add a single record with invoiceiD of say 13
List2 add multiple records bound to list1 invoiceID 13

Is that possible & could I then add a sum on only the 'payment' column in list 3?

Thank you