There are good contractors and developers but the housing boom in Philadelphia has attracted plenty of shady practitioners who are working without permits and using subpar demolition and construction practices. I speak to Jason Sherman who’s produced a documentary on the topic called "Cutting Corners" which shines a light on how these practices impact a community with a focus on neighborhoods in Philadelphia.
https://cuttingcornersfilm.com/
https://www.facebook.com/groups/RiverWardsLandICoalition/
