Hi, we have a 2009 Smart for 2, 1750 pounds curb weight.
Towed four down on a standard tow bar.
No brake system due to low curb weight, legal everywhere except California.
Diodes for the lights and brake lights.
12 volt DC charger for the battery off of the 7 way plug.
Can't see it back there except in the rear camera.
Would never know it's back there.