We live in the middle of town in a quiet neighborhood. The coop is a shed in our side yard that has a 4x4' gap between the shed and our chainlink fence with a medium sized fenced in yard. We want to let the birds free range when they're old enough. They would be put inside the coop before dark and let out during the day. Is there anything that could go wrong? We have 3 homeschooled kids, two who are older than 15 and they're home most the day. We also have a dog but she's been around chickens and is very well behaved and she's never outside without one of us anyway. Would there be anything wrong with that? Or should we get a run?
It's better than no fence but animals can still dig under (fox, raccoons, coyotes) and dive bomb (hawks, eagles). Of course the best defense is having them in at night, so if your lifestyle and routine can accommodate that (remembering that sunset changes depending on the season) you'll be good. I have mine in a run attached to the shed with deer netting over the top to at least tangle up a hawk and give them some time to get inside. I also use the add-a-motor automatic chicken coop door because my work schedule is so chaotic and unpredictable I could never commit to ensuring I'm out there just after dusk every day.
Your chickens will go back to their coop in the early eve by themselves. The dangers you face are daytime raptors like hawks. Way to control that, is to provide overhead tarps or netting. Free range is the best. If you provide some overhead protection , it will be good. Remember that a hawk needs to drop down on its prey. It wont land and chase on the ground after it.
Also know that depending on how many chickens you have and how large your yard is...they will TEAR up your yard. Favorite plants, flowers, etc can be demolished in minutes. Unless you literally watch them like a hawk, they will make a mess of things. Free range is wonderful for the birds, just be prepared for your yard to change or fence off areas you don't want them to mess with. A covered run is always a good idea, IMO. That way they have at least a small space to be outside in when you don't want them free ranging. They will need over head cover if you free range them, like suggested. Tarps, nets, bushes, etc, to hide from hawks and eagles.