That is clearly two (2) units on the floor plan above. Yes, I see how two doors can be installed very, very easily. Our construction office would not let this through, as there are clearly two (2) kitchens on the plan. (Raise eyebrows) 3-1/2 baths on each side??
Definite 4 family in the making.
How are the utilities planned? Panel/meter for each floor? HVAC? Water meter(s)?
Perhaps they had/have a zoning issue for parking or ??
