Like AKDoug says towing in Cook Inlet, with its tides, and into the Kenai river can be challenging at times. I am sure other places have their own set of problems so as has been said each tow is different.
I commercial fished the Inlet for many years and made many tows during that time. I built a tow rig after the first few times. I had two 50 foot pieces of 3/4 nylon and an old tire tied in the middle. The weight and flex of the tire really helped to reduce the shock load on both boats cleats.
The only time I needed help getting home was because of a broken rudder yoke. On the radio I heard a boat calling for help as his engine would over heat after 5 minutes of running. Turns out we were close to each other so he limped over to me. We tied them up side by side. He steered, I powered, and us two cripples made it home with no other help