Two invoice types order-related from the same sales order type

Question

Hi experts,
I need to assign a different invoice type to two different items categories regarding to invoice each item with a different invoice rumber range and a different accounting document type (one 'RV' and another 'PF').
Neither of them have delivery.
I' ve assigned in the copy controls from sales orders to invoices the items categories to the corresponding invoice type in order to avoid the items are invoiced by wrong invoice type.
Exem:
item category ZIC1 must be invoiced by invoice type ZF1
item category ZIC2 must be invoiced by invoice type ZF2
I executed VF04 twice: first regarging to create ZF1 and second create ZF2.
1)  If I insert ZF1 invoice type (order-related) by default in the sales orders definition (Sales and Distribution -> Sales -> Sales -> Sales Document Header -> Define Sales Document Types), the item ZIC1 is properly invoiced and the ZIC2 too. But: although I already invoiced both items, SAP laves the sales order opened waiting to create ZF1 for ZIC2.
2)  If I don't fill the invoice type by defautl, the invoicing can't be done because the invoice type isn't determined (VKDFS-FKART empty).
I want to know if  there is any exit to change the values of VKDFS entries for each item of sales orders before to process this table with VKDFS.
Thanks in advance,
Aupalaura

Answer 1

Hi,
thanks a lot for the quick answer.
But in save document prepare it's not this structure. And the field for save the invoice type by default is at header level FKARA (in VBAK table).
Anyway, I'll check it.
Regards,
Aupalaura