Generally speaking, the poultry farm is supposed to be sited far from a residential area to prevent it from being a nuisance to the environment. Birds in cages do produce odor and should not be near residential areas. However, deep litter system could be sited anywhere if properly managed.
Also note that it is not good that your farm constitutes a nuisance to the neighborhood because your neighbors will start complaining of the odor from your poultry farm and it is against environmental laws. Therefore as soon as your neighbors start complaining, it is a sign that you need to relocate, get a parcel of land and start proper farming.
Even raising birds at your backyard will not be bad only if you can keep and maintain very good hygiene. Make sure the poultry droppings does not constitute nuisance both to you and the neighborhood. However, there is a limit to the number of birds that could be raised at one’s backyard before they become a nuisance. Therefore, if you are really interested in poultry farming, then plan towards getting land outside of residential areas.
See also: How Poultry Farm Odors can be Tackled