Hi,
The delivery terms are part of the contractual agreements between seller and buyer.
In principle the parties are free to agree whatever they might consider as necessary in order to pursue their commercial interests.
The terms of delivery have to be declared in a customs declaration for release for free circulation in order to allow for the correct determination
of the customs value of the imported goods which is also used as the basis for the determination of statistical value/ value for VAT.
You can check CDS completion guidance of D.E 4/1 and 4/14.
DE 4/14 Item Price/ Amount (Box 42: Item Price)
Thank you.