Housing activists, officials and researchers are deploying new tools to empower tenants, spotlight negligent property owners and curb evictions in U.S. cities.
Nija Swanson, 16, front, and Lamirra Jacobs, 16, work with the housing advocacy group Fight Blight Bmore to document vacant and abandoned buildings along Brantley Avenue in Baltimore, in 2019. Group founder Nneka Nnamdi uses a city grant to give teenagers summer jobs to help create a data set of rundown and vacant buildings.
Photographer: Carolyn Van Houten/The Washington Post via Getty Images
The first words on the sign — “VACANT PROPERTY” — posted on the front door of a boarded-up rowhouse in Baltimore’s Upton neighborhood may overstate the obvious: The two-story brick home, its front steps sandwiched between tall weeds and a pile of garbage, clearly hasn’t been inhabited for some time. But the QR code sitting in the sign’s bottom right corner is a window to a trove of more expansive information about this building.
Scanning the pattern with a smartphone camera directs the user to a city web page linking to databases on property ownership, building permits, pending court cases and more. While this information is all publicly available, not everyone knows how to navigate these assorted city and state data portals. 

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