I think its wise to invest in a small fire extinguisher in the car and learn how to use it. Its perhaps a common mindset owners regard this as un-necessary or a blardi waste of money.
I keep one in the kitchen and have trained my family on using one..
I believe faulty or deteriorated electrical wiring inside a car is a likely cause of fires. Sometimes I see those car accessory shop rambos how haphazardly do wiring..downright risky!.