* Take your unit with you whenever you leave your car.
* Remove the suction cup mount from the windshield and wipe away any telltale marks.
* Better yet, ditch the suction mount altogether and buy a friction mount. These weighted mounts grip nearly any shape dash and are easy to hide under the seat or in the glove compartment. They don’t fall off the windshield or leave suction cup marks behind.

This is my favorite type of GPS mount. I can easily grab the entire mount/GPS assembly and place it on the passenger seat before I pull into a parking lot, ensuring that no one sees me disconnecting and hiding my GPS.