What could $20 million buy? Little more than this East New York site (adjusted for size), with much lower development rights
The Spring 2009 Massey Knakal sales Journal, covering the second half of 2008, indicates that a 20,000 square foot lot in East New York sold for $3.45 million, to support affordable housing.
The segment of the Vanderbilt Yard at issue is 495' x 200', or 99,000 square feet, 4.95 times larger than the East New York site. If you multiple the East New York price by 4.95, it comes out to $17.08 million.
The East New York site only supports 60,000 buildable square feet. Multiple by 4.95 and get 297,000 square feet. The Atlantic Yards arena block, of which this segment (Block 1119, Lot 7) would be at least a third, would support an 800,000 square foot arena and at least 1.5 million sf in development rights, according to the City Funding Agreement. (The towers on the area block, as approved, were supposed to contain 2.69 million square feet.)