In a T&M contract dispute, the single most important documentation supporting the contractor's invoices is usually:

Giải thích

Because a time-and-materials contract bills for actual hours and materials, the contractor's ability to justify and collect on invoices depends heavily on accurate, contemporaneous records: daily time sheets of hours worked and detailed material logs backed by receipts. Without such documentation, T&M billings are easily disputed. A license copy, a liquidated damages clause, or vehicle photos do not substantiate the actual labor and material costs charged.