Property R-4 but too small to build?

[Russell R Massey]

Hello! Thank you for your insight!   

I am looking at a corner lot. It is zoned R-4 and had one of those corner stores on it 50 years ago. It has been vacant for 40 yrs. 
It is in the City of Atlanta Proper in a well established R-4 Neighborhood.  It is a total of 1,048 SF lot. It is 23'x46'.
With R-4 required setbacks for new construction, I do not see how anything can be built. 

So, what can I build there?
Do you know of any instances where someone built something in a similar circumstance?