Keeping Cat off Car

Question
I am finding my neighbor's cat on top of the roof of my car late in the evening.  I have a new car which I take pride in, and worry the cat will eventually scratch and mark up the car.  Is there anything or any way to deter the cat from climbing onto of my car?   I need HELP  !!!

I have not spoken to my neighbor yet, but I guess I will have to bring up the subject without upsetting them.

Any suggestions would be greatly appreciated.Thank you
Marie

Answer
Sorry about taking long to answer your question, my internet server has been down. I suggest using a small water gun to spray the cat with a little water when you see the cat on the car. I dont think theres any thing really the neighbor can do about it.