The DuPage Flight Center will provide the ISP as approve small purchase under sole source conditions a DuPage Flight Center "Fuel Price Program" form documenting any changes in price per gallon charges. The DuPage Flight Center will charge the ISP a per gallon price for fuel at the rate of Sellers 2000 gallon per-purchase fuel price program as indicated on the DuPage Flight Center Fuel Price Program document in effect for the date of purchase. Such cost shall not include sales tax pursuant to the ISP's tax exempt status under #9-987-7090-0237. The DuPage Flight Center will provide a monthly report of the ISP's fuel purchases, showing the date, invoice number, total sale amount, and remaining balance of the deposit. Individual fuel tickets/receipts will be provided at the time of sale showing the price, gallons sold, and individual ticket total sale. The DuPage Flight Center requires the ISP to make advance payments. The DuPage Flight Center will apply any prepayments to the ISP's current balance and reduce the balance each time the DuPage Flight Center provides fuel to the ISP. The payment voucher will state "fuel is being procured pursuant to an agreement the terms of which require advance payment." The estimated spend for this procurement is $60,000, not to be exceeded without a change order.