This article examines the role and importance of calculative practices in the process of establishing a global property market. We argue that these practices have contributed to the transformation of the property market into a calculable relation which makes it possible to perceive and assess the real estate market and its objects internationally. Comparability – which includes the transformation of social, political and economic conditions into numbers – has created the context in which investment decisions take place because they suggest transparency and calculability. These practices are created and shared in a network of global real estate professionals and go along with strategies of territorializing and delineating markets. Yet, as we will argue, some local characteristics prove to be persistent and difficult to handle in global calculations. Thus, assessing global real estate markets still implies the challenge to combine local knowledge and global calculation.