Step 3 – Prepare the Necessary Supporting Documents
Supporting documentation, such as purchase orders, receiving reports, invoices, etc., must be retained according to standard retention rules, and made available during post-audit.
The Agency Transaction and Submission Requirements 
reference sheet identifies which document type is required for a particular transaction
type and whether a document must be submitted for approval before processing the transaction.
Transactions with the same document type may be entered on the same document. Documents are used to total transaction amounts and reduce the amount of paper used. Similar documents may be grouped into a batch to streamline entering in USAS. Batch information is entered on a Batch Header form and is common to all documents in the batch.
The following diagram illustrates the relationship between batches, documents and transactions.
