Four down tow "bars"

Yep, you'll need a "base plate" (hardware that connects the car to the tow bar), a tow bar of the same brand as the base plate (preferably one that mounts and stays with the motor home and that has the capability to connect to the car at different angles), light hook up to enable you to activate the car's tail/brake/signal lights from the mh, AND (most importantly) you will need a good supplemental brake system for the car.

The "Roadmaster" web site provided above by JW above is an excellent place to start.

Good luck

Ron