A purpose or event must be given on all vouchers for travel, food, or lodging. Lodging and travel are big audit areas for the IRS.
Itemized receipts are needed for meals and lodging expenses.
All items need to provide the answers to - who, what, where, when, and why.
If a personal check is used as a receipt, submit a copy of the front and back of the cancelled check or something from the bank to prove that the check has cleared.