Cars can be pushed away when there is no one in it so adding the ability to engage the handbrake would stop that making them a viable method of transport in rust as currently they require too much space and materials and are far too easily lost due to people pushing them into the ocean or something.
Also being able to drift would be a cool feature to.
Handbrake would also prevent people from doing the glitch where they place 2 foundations, a door frame, and a double door to break a car, by pushing it into the door and closing it repeatably. Love this idea!
Breaking a car should cost more then 350 wood.
Cars are OP, secure your vehicle.