My ex-neighbour had 20 hens and 6 ducks. He called them free range, but they were all kept in a small pen. The stink in the summer was awful.
He denied causing a rat problem, and tried hanging his feeders from the roof of the pen (the ducks would try to fly out so he had wire over the top). Trouble is, he'd lock them in a shed at night then refuse to come out if I called him when I'd see rats in the garden (I put the dog out several times a night and he'd go frantic after a rat). He still wouldn't believe me when we'd trapped one and showed him (blamed our dog!).
Then he got cockerels. Oh God. The noise was awful. The pen was under our bedroom window and would start at 4am. If it stopped after a while it wouldn't have been so bad, but it would go on all day and as we both work shifts it made us really ill with lack of sleep.
Eventually another neighbour (I assume) reported him to the council and he got rid of the whole lot. I've never been so relieved. And we've not had a rat problem since.
Before him, we had a lovely neighbour a few doors away who also kept hens (and quails). The hens would roam in the field behind our houses and come into our garden (through a hole in the hedge that I didn't want to fix as I'd get hedgehogs as well as hens visiting) when I'd sit outside with a cuppa and a few biccies after a night shift - I used to love feeding them by hand and giving them a cuddle (they make great pets for kids). He didn't keep many, never had a cockerel and interacted so they were tame. Sadly he passed away and his birds were given away. I still miss having my afternoon visits.
I would love to keep a few hens and am all for people having them (especially if they re-home ex-battery hens), but so many people go into it willy nilly and don't consider the work (like any other pet, I suppose). They get them and then can't be bothered to look after them properly and that really winds my clock.
I yearn for a perfect world where people look after their animals and consider their neighbours. It's nice to come here and see people firstly asking for advice and secondly showing consideration to others. If only everyone was like some of the posters here. I'd love both you and your hens as neighbours.