Also worth noting they slow down laying in the winter, eggs are few and far between. In warmer months they will lay an egg every day or two, so with three chickens you'd get likely about nine or ten eggs a week during the warmer months. Not really a big haul to share with the neighbours.
As said for me it's the sheer volume of shit, the work, and I guess cost, involved in keeping them and the cleaning up after them, the mess they will make of the ground, you will need to be scrupulous with your kids hygiene, and the land will be totally barren , and the fact you need holiday cover, someone to look after them, rather than the noise, but they are not in close enough proximity to my house for me to comment on that, I think if right next door it would be an issue.
My neighbour had to put an electric fence round hers, as the foxes will dig under given the chance and get in, and minks, which are more common than you'd think, kill them for sport. By decapitation.
Chickens will also dig under the fence to get out. I've often had chickens escape into my garden and catching them is a pita.
A friend of mine was desperate for some, had always been her dream apparently , and was moving to a rural location, so I took her to next doors, as I look after them about two months of the year, and it put her right off when she realised the mess they make.
Also to be honest, I really can't tell that much difference, if any, from a freshly laid egg and a supermarket one. I'd challenge anyone to do a blind taste test and be able to spot the difference.