I suggest you buy an incubator and put a roost or two in an old metal shed. The chickens will forage everywhere, roost at your place at night, and it’s not your fault the wild chickens have chosen to occupy your old shed. There will be attrition, keep collecting the eggs and incubating them. Eventually you’ll end up with wild chickens that roost in trees throughout your neighborhood. Laugh heartily when the city tries to take the wild chickens to the dog pound and enjoy hunting eggs in your neighborhood, it’s like Easter every day.