Well, I'd think that the fox might try to catch a bird or two fo those that come to your place for food. If any mice or other small rodents live nearby, the fox will hunt those also.
However, our member, Words, has a great site and much experience with urban foxes. There's lots of information on Words' site (www.permuted.org.uk) and contact information if you still have questions.
There's not a lot of traffic on this forum these days but I hope that the link will help somewhat if Words doesn't see this thread before then.