John, a new client of yours, is a self-employed caterer. John drives his personal van when delivering catered meals to customers. You are preparing his tax return and asked him to provide the number of business miles driven using his vehicle. You are planning on using the standard mileage method to calculate John's deduction for transportation. John replies that he "doesn't really keep track of mileage", but he guesses he used the van around 20,000 miles for business. Read the following IRS publication and make a determination as to whether you would allow John the deduction.

Where does the deduction for mileage for a self-employed person go on a tax return? How much is the deduction? What other form must self-employed taxpayers with positive income prepare? What is this second form for?