Developer of "100% affordable" 535 Carlton now offers free month; net rent for 1BR = $2,474, 2BR = $2,975
Six specific units are listed on Streeteasy, but as the listing for Unit 520 below indicates, "various one bedrooms and two bedrooms are still available." That implies that the 36 studios at $2.137 and the seven three-bedrooms at $3,716 (subject to notable scorn when the story of still-available units blew up last November) may be taken, or at least aren't being offered now.
Interestingly enough, because the rents (see lottery ad) are set by a government program, limited they must list the gross rent, not the net rent, which is typical advertising-speak when incentives are offered.
By my calculation, the net monthly rent for a two-bedroom unit over 13 months is [(3223 x 12)/13], or $2,975. For a one-bedroom, it's [(2680 x 12)/13], or $2,474. Of course, after a year, the discount expires.
Size of units
Note that the two-bedroom is listed at 973 square feet, which is not huge for a two-bedroom on the open market, but certainly larger than required under city guidelines, which allow affordable two-bedrooms under 700 square feet! Another two-bedroom listed (see below) was 964 square feet. (I think the one listed for 1,100 square feet was a mistake.)
In fact, as noted in the screenshot above right, the New York City Housing Development Corporation's M2 (mixed middle-income) program, which approximates the configuration (if not all the details) of 535 Carlton, allows much smaller units.
One reason the apartments haven't rented easily is that they're not cheap, and middle-income households have other options. Another is that relatively few people are eligible in the first place.
Below are the income "bands" as of 2017. For a one-bedroom, the minimum is $93,258 for one or two people, and maximum is $110,220 and $126,060, respectively. For a two-bedroom, the minimum is $111,909 and the maximum, depending on whether there are two, three, or four people, is $126,060, $141,375, and $157,410.