I was always told you fix a boy long before they spray otherwise they will continue to do it even after. The smell will always attract them back. He would have to become an outdoor only only cat here. Everything he peed on would go in the trash because no matter what the smell NEVER goes away. You will think it does but it will get hot or a room will get shut up etc and there it is back again. It can also attract other cats to begin marking their scents as well.