What does "Do you have evidence to support business use claimed?" mean?

[jamlawxx]

I counted my car as something used in my business since I was a delivery driver, but it's asking if I have evidence. Does that mean evidence that the car was used, or evidence that I in fact worked for the company?

[Patrice · Accepted solution]

Evidence to support your business claim is documentation to support the information that you are entering on your return.  The best evidence to support your business use is a written log of the business use of the vehicle that includes mileage and travel itinerary. You generally must have documentary evidence, such as receipts.  

Evidence that is used to support your claim would be considered adequate if it shows the amount, date, place, and essential description of the expense.  Cost of each separate expense. For car expenses, the cost of the car and any improvements, the date you started using it for business, the mileage for each business use, and the total miles for the year.

You should keep adequate written records to prove your expenses or have sufficient evidence that will support your own statement. You must generally prepare a written record for it to be considered adequate. This is because written evidence is more reliable than oral evidence alone. However, if you prepare a record on a computer, it is considered an adequate record.

You should keep the proof you need in an account book, diary, log, statement of expense, trip sheets, or similar records.