Cheapest way to build Small units or duplex? Phoenix

[Lindsey Keller]

I have an 10,000 sq foot R3 multi fam lot in the heart of Phoenix.  I have a front house, but room on the backlot to build 2 units.  Either 2 separate or a duplex. 

What is the cheapest way I can do this?  Looking at - Prefab, Modular, Manuf, Shipping containers, stick build, steel buildings

I want a modern look, big windows etc. I will be renting these out and my goal is to get $1500 each. 

Any knowledge, companies that do this etc? (Under 100K total would be awesome as I need to consider the lot landscape and utilities to the units)

I hve looked at even Amazon and considered Allwood prefab houses... not sure if anyone has done that?