What if you used someone else's vehicle to travel to work?

All vehicles show on my petrol statements and IRP5. What supporting documents would I need if SARS Audits me because some of the vehicles I used over the years are on my fathers name but my company knew this.

This should not be a problem as long as you kept a logbook of your business travel and can justify to SARS the total mileage you travelled split between business and personal.