@cynthiaeoneill-g 

A Sched C would not be used for someone who is an employee. Is there someone able to review how to run an S Corp with you and this client? Because, based on the activity you describe for the personal vehicle and what you are trying to do with the data, both you and the tax payer would benefit from a review with someone more knowledgeable for how to run the S Corp operations per the IRS regulations that apply. It is never wrong to be mentored.