If you decide to rent a car, opt for a vehicle which comes with a built-in GPS device instead of a portable one. Since it is not safe to leave portable GPS devices in the car when the car is parked, inevitably you have to hide it more times than you think. It is not just the putting it away every time; you also have to find a good spot, secure its position, put the charger on, turn it on, turn it off etc. You get the picture.
So, in order to avoid the hassle of having to put it away every time you get out of the car, and put it back on when you get in, try to rent a car with a built-in device.