Get some regular balloons and fill them a little more than halfway with water. Then add food coloring or some of a Koolade packet for color. Take Barbasol shaving cream and fill the rest of the ballons with it. Take a stroll outside and bomb the shit out of her annoying ass car. I would almost gaurantee that she doesnt park anywhere near you again and she will probably get the hint about the alarm. In the case that she doesnt, deflate her tires and rub shit under her door handles and leave a printed note about her alarm.