In an extreme situation like that, my best advice is own a vehicle that doesn't 'look' like it has a system, no low riders on lo-pro's, 18's or 20's. That means factory wheels, paint, hell even put a my kids an honor student sticker on the thing. Think rusty Ford Tempo. Then never, ever, play it loud around your area.
Otherwise I do not know what magical answer you expect us to come up with. You know, basically, what it takes to install, and then uninstall an entire system.