(f) Prompt payment for commercial purchase payments. The contracting officer shall incorporate the following standard prompt payment terms for commercial product and commercial service contract financing:

(i) Commercial advance payments: The contractor entitlement date specified in the contract, or 30 days after receipt by the designated billing office of a proper request for payment, whichever is later.

(ii) Commercial interim payments: The contractor entitlement date specified in the contract, or 14 days after receipt by the designated billing office of a proper request for payment, whichever is later. The prompt payment standards for commercial delivery payments shall be the same as specified in FAR Subpart 32.9 for invoice payments for the item delivered.

(g) Installment payment financing for commercial products and commercial services. Installment payment financing shall not be used for DoD contracts, unless market research has established that this form of contract financing is both appropriate and customary in the commercial marketplace. When installment payment financing is used, the contracting officer shall use the ceiling percentage of contract price that is customary in the particular marketplace (not to exceed the maximum rate established in FAR 52.232-30).