Import documentation

Yes Bill of Entry is an essential documents to evidence the goods have been imported, Exchange control copy has to be submitted to the bank as proof of imports. Advance payment can be made without B/E subsiquenlty you can sumit B/E within 3 months. You can discuss with your banker and they will pemit the same

For advance payment paid to foreign seller, we don't require Bill of Entry at that time. You just Produce purchase order along with Form A (For Foreign Payments) to you bank with complete detail of seller.

When the said good is imported in india you can pay the balance amount with Bill of Entry and produce copy of earlier payment at time of making full and final payment