We tow our 4,200# Jeep Rubicon behind our FR3 30DS. I'm always looking at the rear camera to verify it's still attached.
We found the "Ready Brake" system at the annual Quartzsite show and like it - seems to do the job: NSA RV Products - Ready Brake and Ready Brute Home
A cable is attached to the Jeep's brake and connects to the Ready Brake with a detachable wire. There's an indicator light that is run up to the driver area that shows when the brake is activated. When you step on the RV brakes the force of you vehicle pushes towards the RV and then the Ready Brake pulls the wire to and applies the brake on the towed vehicle.
We started with a Roadmaster Falcon 2 tow bar, but converted over to a 10,000# BlueOx towbar found in a garage sale for just $25! I prefer the BlueOx for disconnecting as the Roadmaster Falcon 2 always seemed to bind.