This paper examines German local health insurance funds’ housing surveys in the first two decades of the 20th century, highlighting their distinctive investigative style compared to official housing statistics. It discusses the tension between comprehensive housing statistics and localized “individual investigations” and places this within the context of monographic surveys. Individual investigations were considered superior, particularly in terms of their ability to comprehensively address the complexity of the “dwelling” as an epistemic object. The paper focuses on a paradigmatic individual investigation led by Albert Kohn at the Berlin local health insurance fund. In an innovative fusion of numerical, narrative, and visual modes of representation, Kohn constructed compelling persuasive chains of perspectives on the miseries of the housing situation. The final section explores subsequent works influenced by Kohn’s survey, especially in Strasbourg and Breslau. In Breslau, a distinct investigative style emerged, with polemical essays integrated into the housing survey, turning it into a journalistic campaign against the inactive city administration and the indifferent press. This demonstrates the richness and distinctiveness of the health insurance funds’ survey methods compared to state or municipal housing surveys and statistics.