Projects - Intercompany model

Hello everybody, I would appreciate your recommendations about the best way to model the following scenario:

Scenario Project - Intercompany (site 1, site 2)

Site 1 needs a special item for a project, this item is bought by Site 2

Site 1 places a purchase order (PO), for Site 2 that becomes a sales order (SO) for Site 1

The SO at Site 2 generates a PO for a particular supplier, the supplier will delivery the item directly at Site 1

What will be the best way to model this and close the circle between the two facilities? Any recomendation will be appreciated.

Many thanks!!!