Stray cat driving me nuts! Help!?

Do not be persuaded to take him to a shelter or call animal control. Ask his "owners" if they can get his neutered. This should help with the spraying and the need to be dominant (when he struts and hisses at your cats). If you need to, when he comes around your house, scar him away or spray him with water. You can also talk to his "owners" about the problem. they will probably not be too upset, if you talk to them politely about it. They might even be able to train him to be an indoor cat f it comes down to either him being an indoor cat, or him being a "sleeping" cat. They might be able to do this by keeping him inside overnight and then letting him out as soon as they wake up. This way he will slowly get used to being inside for long periods of time. After he seems comfortable inside overnight, you can extend, or shorten you need to, the time inside. But do not go too fast for him. First, make sure he is comfortable at the time spent inside before lengthening it.