Q: Over the past couple of years, foxes have multiplied and are now residing all over our neighborhood: under porches, under sheds, etc.. We find carcasses of their prey in our yard continually. What to do?
A: Like coyotes, foxes are very adaptable to human surroundings. If your neighborhood makes a concerted effort to keep pet food and garbage away from the animals, their numbers will decline.
On a side note, coyotes typically out-compete red foxes in a shared habitat. Coyote numbers are increasing in metro Atlanta, so your fox problem may be supplanted by another predator whose presence you may not like either.
The only decisive option I see is for you to hire a professional wildlife control company.