While the it is always debatable whether or not a borrower can purchase a home in their city, I find the below map, published along with an accompanying article by the Washington Post, to be very interesting.
http://www.washingtonpost.com/blogs/wonkblog/wp/2015/03/08/map-the-salary-you-need-to-buy-a-home-in-27-u-s-cities/?tid=sm_tw @washingtonpost
http://www.washingtonpost.com/blogs/wonkblog/wp/2015/03/08/map-the-salary-you-need-to-buy-a-home-in-27-u-s-cities/?tid=sm_tw @washingtonpost