With the std IV, the expected quantity and amount based on total GR quantity (per PO item) is presented in MIRO.
With GR based IV, there are distinct items for quantity and amount presented per individual GRN in MIRO.
It's an item level setting on the PO, which you could default from master data e.g. PIR if desired.
Gr Based Invoice Verification : In this a separate invoice item is created for each delivered partial quantity.If we make the allocation with the purchase order system then propose more than one invoice item as a default if more than one partial delivery has been posted for the po item.
If we make the allocation using delivery note the system proposes exactly the po items from this goods receipt, plus the the quanties posted.
using gr based we can assign each invoice item uniquely to a good receipts item. Good receipt and invoices matched in po history
In Gr based invoice qty should not be greater than actual delivered qty.
Purchase Order Based Invoice Verification : In this system generates one invoice item in the item list for each po item. The system provides quantity to settle in as difference between total d livered qty and thee total invoice qty.
If we make allocation using delivery note the system determines the relevant po items with their total qty to settle-in the same way as if there was a reference of purchase order.The system will not propose qty relevant in delivery note.
If there are several good receipt the purchase order history will not tell you which invoice came from which vendor.
if you have unflagged the gr based invoice verification in xk02, me12, me21n, the system will allow you to create invoice.there is no seperate configuration for PO based invoice verification.
If it is not gr based invoice verification, select the option of goods service items+planned delivery cost in the miro screen, you have to enter the values and qty manually.
this is possible only in the case of IMPORTS in MM, where we will pay the customs duties first to the custom dept, then do the gr and invoice respectively.