Hardware costs for flat-towing (brackets/wiring/tow bar)....

On more question: many mentioned running a wire to help keep tow vehicle battery charged from the RV alternator system. Assuming this is since the tow vehicle ignition is on the "ON" position the whole time while traveling? So, the 7-pin hookup does NOT account for this, right? I was going to have my brother assist with this if and when I go this route, and just wanted a heads-up.