Carl Contractor, the owner of a construction business, comes to you to prepare his return for the first time in 20X7. Carl doesn't use any accounting software or a bookkeeper, but he claims he keeps track of all his expenses in an Excel spreadsheet and tosses his receipts and invoices in a box. Carl says, smiling, "check this out, all the receipts are in chronological order." The largest expense on Carl's P&L is for heavy equipment rentals, and his spreadsheet indicate she uses the same rental company for all rentals. A December invoice from the rental company, on bright pink paper, is on top in the box-o-receipts. After a quick peek in the box, you do not see any other pink pages. Can you rely on Carl's spreadsheet for this expense? What if you flip through all the invoices and the invoices matched up to the penny