I would go with one like the SMI stay n Play or the Roadmaster Invisi brake.
These are installed into the toad. You do not have to do anything other then turn them on. My unit is wired off the battery before the battery disconnect.
Units like the Brake Buddy require the unit to be moved out of the driver's area prior to driving the vehicle.
It is best to have an auxiliary braking system if you are any where near the max weight of the combined vehicle set up. Lots of people will say they are required by law which is not true in most states.
