Welcome to my What If I had an apartment tower. For the sake of rationale, I will assume Smithfield St which listed for sale on a website for an undisclosed price. The first floor will have a part of the rental office, mailboxes, and access to the apartments. The second floor will have the individual office suites of any major employees, Floors 3-30 will have the apartments while a 31st floor will be built for the penthouse.
Each apartment floor will have a 2BR apartment, two Studios, and three 1BR apartments. This will be a total of 6 units per floor, and 28 floors of apartments for a total of 168 units.