Electric shock systems would have to be a no-no (unless enclosed and limited like rat zapper ) due to other wildlife, birds, our hens and cats. Same for poison ..inhumane and into the food-chain. Out here in the sticks there's no concern re neighbours being bothered by lights. The idea of parking on a deterrent mat sounds good..but outdoors in wales when it rains the area around the car might sit in water if not draining as fast as falling so any contraptions have to be an inch+ off the ground and under the car. Current game plan is to chuck a cable reel under the front with sonic repeller and (now) a 10W LED floodlight. I may add a couple of rat zappers in the adjoining barn but with woodland adjoining the parking area there is no way of removing all rodents.