In turn key construction, the interior (down to the carpets and cabinets) are finished.
It typically costs between $64,575 to $86,100 per unit to construct a 12 unit apartment building having a normal foundation with a full basement, efficient doors and windows, all appliances, and "turn-key" finishing (using mid range materials).
Costs vary greatly by region (and even by zip code). To get free estimates from local contractors, please indicate yours.