Sorry to hear you are having fox problem. I have just dealt with the same situation. I had a red fox living under a shed about 50 feet from my hen house. I tried everything for about 3 months to get rid of the beautiful guy...he just kept coming back. I blocked off the shed entry ways, tried coyote urine, scared him away, to no avail. I ended up hiring a trapper, that did use a leg trap. He set it up in the early evening, and by morning, the fox was in the trap. He had to be shot, which broke my heart, but only way to keep my chickens, dog and cat, and my family safe. Trapper set trap again, just in case, and the next morning, we had a female red fox in the trap! Must have been planning a family and getting a den ready. Thank goodness she was not pregnant (at least she didn't appear to be) and she was not nursing, so no kits yet. She was shot by the trapper....It broke my heart, they are beautiful animals, but they will kill your chickens and keep killing, plus, you risk rabies and other diseases. Hire a trapper, a licensed trapper- they know what they are doing and will do the job properly, and quickly....
Now, my chickens free range, my kitty goes out safely, and everyone is happy again....
Hopefully, no more foxes will move in! If they do, I know a guy......