I have a disconnect switch for my house batteries which I located in the outside compartment to the right of the door - right next to the batteries. It was one I had in the battery bank in my boat and is an easy on-off turn switch for big loads. I have not installed a switch on my starting battery because I worry about shutting down the engine computer every time. I don't know the long term effects of turning the computer on and off and it having to relearn the engine settings every time when it may not be designed to do this. It is an expensive piece of equipment to replace.