If you only want a few you could get point of lay hens, two or three will calm down very quickly and start laying right away. Eglu sends them with their setup I forget which hatchery they use- you order them at the same time you order the coop, and feedback has been that they are very nice tame birds.
I also second the opinion that just two or three reduce cleaning problems, don't damage the yard as much, and will produce plenty of eggs. If you are lucky enough to have pleasant neighbors, why would you want to risk a good thing by overdoing it?
I also want to add that in the city it is also best to have a separate (safe) enclosure for them. I have a playhouse coop- which has an enclosed covered run attached. It sits over in a corner of the garden. You can always let them out in the yard when you wish, but they have their own space and do not suffer if you need to keep them penned up for any reason. (ie. chickens in a clean pen in the corner of the garden that the children can give their scraps to are a charming addition to your outdoor barbecue - chicken poo on the table charms no one). And the peace of mind when my sister visits with her dog who "wouldn't hurt a flea" is priceless.