[bengebre]

http://www.deptofnumbers.com/nyc/home-sales/new-york-city/ - An analysis of New York's property sales records by borough and neighborhood.

I'm trying to build a openly defined price index for residential sales across the city.

[lefstathiou]

check out the publicly available figures from radar logic, they aggregate residential real estate transactions in the boroughs and NYC and publish a daily price per square foot. an interesting technology they havent figured out how to capitalize on but relevant to you nonetheless.