Cats are awesome. They are beautiful and smart creatures and make perfect houses pets. When one of our cats got sick we spent $5000 bringing her back to health and would have gladly spent another $5000 without thinking about it.
Sorry to hear you have cats pissing on your car. I've never once had that problem but there seems to be lots of videos with advice at
how to stop a cat from peeing on your - YouTube
Good luck! And please don't hurt the kitty.