The actual decision as to whether they will be rentals or condos is occasionally made right before a building opens.
Basically, the developers look at the market for each and then decide which is most profitable, and whether they want cash now (condos), or over the course of the long run (apartments).
Yet another scenario is that the present developers sell the entire building to an entity (i.e. developers get cash now) which decides that it would like cash over time.
The developer needs to make such decisions when it comes time to buying appliances and installing finishes, not at the present rough construction stage....
They also have some flexibility re: the actual number of units (apartments or condos), if all is going well with DOB.
Folks are going to talk about such topics here, at this upcoming conference: http://thebrooklynsummit.com/
The eight-story apartment building going in on the corner of Franklin and Eastern Parkway at 341 Eastern Parkway is up to the fifth floor now. Construction started in the fall, and is supposed to be completed by the third quarter this year. There are 64 units planned, plus retail