In my Saturn pulling the fuse isolates most of the systems that would draw down the car battery. Before I installed an extension to a remote fuse under the dash I would occasional be lazy and not pull the fuse for short trips. True, there was no problem as the battery could easily handle the one or two hour draw. However, once, either because the battery was weak or I left the radio on or whatever, I stopped to find the car battery "dead". After that experience I made the fuse extension and ran it to the dash. I see in the RV magazines that you can now purchase a similar product with a switch. I just shorted out a 30amp fuse, soldered an appropriate wire to the test points on the fuse, put the wires through the firewall of the car, and placed a new 30amp fuse in line. Jerry Built but it works for me.
Happy Trails.