About a year ago I saved one beautiful cat from dying cause the whole litter of cats were rejecting him and attacking him. I live on first level in a apartmant and I knew that He is going to go out and explore bcs there was no way of keeping him in House with closed windows 24/7. Everything was fine untill a month ago when He figured that He can go further then usual. Sometimes He doesn't come home for 12-15 hours, I go around to find him, yesterday I was looking for him 2 hours but He came home a little bit after me coming home, also He got into a fight with other cat and I had huuuge vet bill. I am sick worried what If someone steals him or attacks him I would do something that I wouldn't like. I'm attached to him too much. What to do?? I was thinking about gps, I dont know anything else that I can do?