Are there any rules here about whether you can keep chickens as pets in urban areas?
Keeping chickens is very common here, I wouldnt worry about it if I was you. You can always ask your neighbours if it would bother them, that way you'll avoid any problems.
My advice would be to get a coop of chickens, but no rooster. Chickens aren't too noisy, so they won't bothere your neighbours, but a crowing rooster at dawn probably would get annoying quite quickly...
Yolandi is right, its the roosters that are annoying! If you are only keeping chickens for eggs, then you don't need a rooster anyway.
Thanks everyone! We chatted to the neighbours and they don't mind us getting chickens at all! Where is a good place to buy them from.