English to Russian Bus/Financial Business/Commerce (general)

The buyer will pay to the seller the purchase price as follows:
a) pre-payment 60% (in words: sixty percent) of the total amount, i.e. 17196,- EUR (in words: seventeen thousand one hundred ninety six euros 0/100) before signing the contract, at the latest December 20th on the basis of proforma invoice.
b) rest of the payment, that is 40% (in words: forty percent) of the total amount, i.e. 11464,- EUR (in words: eleven thousand four hundred sixty four euros 0/100) before hand over of the machines, the latest at time of delivery of goods on the basis of the tax document (VAT invoice) issued by the seller.
P.S.Текст контракта составляли поляки, так что если что не так, звыняйте...