Yesterday's Wall Street Journal has an article on tough neighborhoods to build in (Housing stalls in urban hot spots," by Laura Kusisto, 7/17/2017). Fishtown, a Philadelphia neighborhood is third toughest neighborhood in the US, at least according to the article. What makes a tough neighborhood to build in?
Residents of these older urban neighborhoods generally have resisted newcomers, complaining about congestion and public transit and seeking to preserve architecture, sunlight and views.
There is a nifty chart with the article showing that Philadelphia generally is slight tougher to build in than average. A sidebar article, not online that I can find, "A Look at Fishtown area in Philadelphia" goes into some detail.