We had the same problem, although we know for sure its a cat, we've never actually seen him in action. So we can't tell which neihborhood stray it actually is. What worked for us was orange peels. Apparently they don't like the citrus scent. However its not by any means a one time fix since they seem to do the trick for around a week and a half to weeks at most and then you'll have to eat some more oranges and put the peels down. Some good suggestions here might have to try mothballs in a container it might last longer.