This December article from Josh Cohen at Crosscut is worth taking a looks back at. It very clearly articulates some of the most important details of the Seattle housing shortage.
"The availability (or scarcity) of affordable housing is literally shaping this city’s future, and to better understand this complex issue and its impact, you need to know how affordable housing is defined, why its shortage is being called a crisis and what city officials are doing to try to keep Seattle livable for everyone."
What makes city livable? What properties + spaces will have to change to make room for the more than 70,000 units officials say Seattle needs to provide for affordability? Will can we do to include families and the elderly?
There are some pretty differing opinions on how to fund affordable housing, who gets to live there, and where new units will get placed. Take a look, Cohen gets to most of the meat of the issue.