I carry a tool kit with me when I travel to different tournament locations, and it’s come in handy more than once.
First of all, because flat tires are the most common piece of bad luck, it’s a good idea to have a tire repair kit that includes a heavy-duty cordless 24-volt impact wrench, an air compressor that plugs into the cigarette lighter, a strong floor jack and plenty of tire plugs. Otherwise, take along a set of Allen wrenches, screwdrivers and some sort of multiuse wrenches. Zip ties come in handy too, like for bundling transducer wires that have come loose and that sort of thing. Extra fuses also should go in the kit, although they probably won’t be needed until you get out on the water. I also carry a spare prop for my outboard and a spare for my trolling motor.
For peace of mind more than anything else, it pays to take along everything you might need to get you to the fishing and to keep you fishing.