Issuance of Purchase Confirmation and Manufacturer Designation in Multi-stage Transactions (Manufacturer–Intermediary–Exporter)

I am planning to purchase goods for export. If the transaction proceeds in the following order: Manufacturer → Intermediate Developer (Intermediary) → Our Company (Exporter), I would like to inquire whether a Purchase Confirmation can be issued at each stage to apply the zero tax rate. Additionally, in this case, please advise whether the intermediary or the actual manufacturer should be listed in the manufacturer field of the Export Declaration Certificate.