Good luck working with the city and getting a variance, hopefully they will allow you to get some chicks. A thought with guineas, although they are great for pest control, they too are the great wanderers and probably would not stay on your 10,000 sq ft. They are also noisy and my cause you problems with the city later. 5 chickens will also keep your pest control down for the amount of area you have....just some things to think about....