How to add discounts in landed cost

Hello

we know that we can add the ORA_DISCOUNT or any custom charge name for adding the discounts on Landed Cost with negative amount and create the Trade Operation accordingly. But We have following questions, can you please advise

• Would the PO be created based on the base price or we need to add the discount on this
• How the AP invoice will be created
• Do we need to add the miscellaneous line in AP and match with Trade Operation ?