It seems that duplex is permitted. 

The day after rent is due issue the pay or quit notice, apply late fees as permitted.

The two issues are permits for contracting work.

New tankless water heater All demo and trash to be haulaway by usTOTAL 170K No roofing No Electrical panel upgrade No permits at this point

While Tenant may use and enjoy the Premises to the fullest extent permitted in this Lease, no estate or permanent legal interest in the Property is being transferred or conveyed by Manager to Tenant herein.

In Atlanta/metro, you have to have a "real" kitchen permitted, even in a backyard tiny house. 

Starting July 1, 2022, any STR, whether whole house or partial, will be subject to a Short Term Residential Occupancy Tax and Permit.

Pay up for the right kinds of permits, from which funds are allocated to improving roads, schools, homeless situation, etc. 

Do you have the reserves in case something goes wrong or you need inspection/permits or have to hire a contractor? 

I considered running gas lines along the exterior of the building and installing wall furnaces, but I was advised that gas lines are very expensive to install and require permits.