Tearing down and Building a quad

Hello BP I am a local wholesaler/investor in the metro Atlanta area, with little experience in multi-units. I have a property that is a fire damaged single family and will need to be completely tore down. I want to know what would it take to build a quadriplex on the land? What are the requirements for a 4 unit property? And who in the city can I contact to get all the necessary information. Also I would like to run the numbers with a experienced investor to see if it would be a good deal.