I use fox traps for my business.
You need a trap that is at least 4ft long and about 18 inches high with a locking single door once activated.
a trapped fox becomes a strong animal, so sturdy is the name of the game. I use tent pegs to secure it to the ground.
I use these, they are well made, pay attention to assembly and use additional cable ties to add strength.
Catching foxes in a trap is an art, location is critical, for town foxes I found KFC makes a great bait, a tin of sardines with the oil poured around the entrance and into the trap, the smell brings them in.
Use the bait on the door release cable, avoid touching the cage and bait USE GLOVES ON your hands, if you do touch use some oil from the sardine tin and wipe the cage.
Once caught use CCI SEGMENTED HP to dispatch the fox, other rounds go right through the foxes head and a risk of hitting the bottom of the cage.
http://www.trap-man.com/fox-traps.htmMike
https://eastkent-foxcontrol.co.uk/