We've been thru the tow bar thing before on here. A search will bring up the past threads but I'll give the main points.
Tow bars put ZERO hitch weight on the tow vehicle so the tow vehicle must be much bigger than the vehicle being towed to keep the back end planted and not be pushed around. Alberta law is like twice the weight, so for most Jeeps on a tow bar you would need a truck with a camper on it for a minimum. This is why motorhomes work well.
Also any trailer over 3500# must have brakes on it. You Grand Cherokee my be rated to pull 5000# but the manufactor assumes that any load over 3500# has its own brakes. The brakes on a Grand Cherokee are not big enough to stop itself plus another 5000#.
People do it all the time but its not a good idea, get a tow dolly with brakes or a trailer if you don't have a 10,000#+ tow vehicle.
Oh yeah backing up usually only works if you lock the steering wheel and back straight up. Its also REALLY hard on the tow bar.