You can submit a request for an agreement online through the Philadelphia Tax Center. Here's how: Log into your Philadelphia Tax Center profile.A master purchase agreement is a legally binding contract between buyer and seller, and typically relates to buying and selling goods rather than services. This Master Sales Agreement (the "Agreement") is entered into between the buyer listed on the applicable Purchase Order ("Buyer") and Calimetrix, LLC. A master receivables purchase agreement is a contract between a buyer and seller of receivable accounts that standardizes the contract process. (b) Adjustments to Estimated Base Purchase Price between Closing Date and TRS Payment Commencement Date. Installment Payment Financing. At closing, the seller and buyer sign and record an agreement that sets out the terms for payment of the unpaid purchase price. Grievances relating to the National Master Agreement. The six month entitlement to leave without pay with benefits.