Do It Yourself Towing
Tow trucks are too expensive! I've got a chain and a buddy to do the steering and apply the brakes, so we'll just drag that broken down vehicle home and fix it ourselves. Think of the money we'll save doing it this way!
Not Such a Good Idea
As long as you don't get caught or cause a crash, it might be the cheap way to do things all right. But if you do get caught, count on receiving a ticket and then paying the towing bill on top of that.
The chain is a good for pulling a vehicle out of the ditch, or pulling a disabled vehicle to the side of the road, but its use ends there.
No Passengers Allowed
The first stumbling block in this plan is that your friend is not allowed to be in the vehicle while you are towing it:
Towing occupied motor vehicle prohibited
7.07(6) No person shall tow a motor vehicle if there is a person in or on the towed motor vehicle.
It's a Trailer
"trailer" means a vehicle that is at any time drawn on a highway by a motor vehicle, except
(a) an implement of husbandry,
(b) a side car attached to a motorcycle, and
(c) a disabled motor vehicle that is towed by a tow car,
The biggest problem with using a chain, cable or rope to tow a vehicle is the chance of having to make a quick stop causing the two vehicles to crash together. A proper tow bar will hold the vehicles apart and provide control over the combination.
It is almost impossible to maintain a constant tension in the connection between the two vehicles. The sudden forces involved in taking up slack may snap the connection causing more unintended consequences.
The requirements for a proper trailer connection are found in division 7.07 of the Motor Vehicle Act Regulations.
Let's consider brakes on the towed vehicle as well. Since the law considers the vehicle to be a trailer in these circumstances, if it weighs more than 50% of the net weight of the towing vehicle or more than 1400 kg., brakes are required. These brakes must be self applying or operated by the driver of the towing vehicle.
Make the Right Choice
A tow truck, tow bar or trailer is the safe answer and might end up being the least expensive solution.