And that is all that is required per IRS code - notice must be sent to US Attorney.

(I use Midwest Tax Service - he also owns rentals so keeps a close eye on changes in the tax code). 

Learn about local zoning laws and building codes.

If you don't have a tax professional already that you can trust and rely on to dive into the weeds on this stuff with, that is most critical to your long-term success in using the tax code to your advantage. 

get more micro. we define a zip code as a market. there are about 7 zip codes in the city of columbus that we work in as well as about 15 in Miami. we look at the average housing unit delivered and try to develop under the median and average home or condo where there is a lot of absorption. that is mostly through smaller Floorplan design, smart floorplan design, etc. new construction and development you also have much more control over the overall development just my 2 cents. if you are just buying existing it's going to have some issues 

They will help you navigate the permiting proccess and getting the unit up to code.

If I am correct, does anyone know where this is in the IRS code? 

conversions can be more expensive than new construction sometimes. maybe they can do a studio conversion as a start and make it smaller. there are a ton of strategies and structures but start by studying the market for 2 family properties and getting to know the miami zoning codes. you are the expert not them. ask for compensation 

What do you guys think are the best zip codes in south Florida for fix and flips?

That said my go to 'line' in situations like this is something to the effect of: "Thanks for clarifying that requirement for me, could you point me to the specific section or sections in the code that covers this?"