we had a terrible problem when a new neighbour moved in next door with two cats. They used our garden as their personal WC, and also climbed onto my soft top convertible car roof digging their nails and damaging the fabric roof. we were at our wits end, we could not sit in our garden due to the stink, hubby could not do weeding without getting covered in poo. we went through all the list of things supposed to help, costing us a small fortune! eventually a water gun, super soaker, did the trick, whenever we saw the cat climb on the car, or come into our garden, i would spray it with water, and super soakers can reach a long way, so i had them on the window sills armed and ready, even from a top floor bedroom , they would reach the cat! that was the only thing that helped us, but we moved thank god as they were the bane of our life!