What must be included as part of the Contractor's invoices?

The inclusion of a unique invoice number and the PeopleSoft Purchase Order ID number is essential for several reasons. Firstly, a unique invoice number serves as a reference that allows for efficient tracking and identification of individual invoices within the billing system. This helps streamline processes during audits, payments, and record-keeping, ensuring that both the contractor and the client can easily manage and reference the specific transaction.

Secondly, the PeopleSoft Purchase Order ID number is a key component as it links the invoice to the specific purchase order that was issued for the project. This connection ensures that the invoice aligns with prior agreements and services rendered, helps prevent discrepancies, and facilitates prompt payment. By including both these elements, contractors provide clarity and organization, which aligns with the best practices for financial documentation and compliance.

Other options like general project details, the contractor's name, or summaries of previous invoices, while they may be useful in certain contexts, do not specifically address the systemic need for tracking and validation that receipt of payment necessitates.