I carry 3 plastic bins with lids in my rear storage compartment in my 'C'. One contains 2 white water hoses with a connector and one green hose. One contains 2 slinkies and a connector. And one carries an extra 25 ft. 30A electric cable and two 25 foot coax cables with connectors. At some point in my travels I've needed the extra extension from one of the three boxes at least once.
To make room, I removed the new 700 piece tool set (an exaggeration) and replaced it with a few tools and a credit card in a small tool box. I don't know how to fix anything anyway.