Housing is a complete nightmare in Seattle. It gentrified thoroughly, so working class people have a hell of a time finding anywhere to live. It's the same problem across much of the western world, but it is amplified in places where there are a higher percentage of highly compensated workers. See, London, San Francisco, and to some extent NYC.
If you import a large whack of highly paid people fairly quickly, it throws the economy out of balance, right? Then you get politicians who listen to every grifter who comes along, and you get "solutions" that mainly profit the grifters, but rarely fix anything.
As soon as Amazon proposed HQ-2, things collapsed, and as of last fall Seattle paradoxically had a high vacancy rate, and no affordable housing (a snappy little $900K condo sitting empty does very little to help the bus driver who's looking for an apartment for his family, it turns out). I think things may be calming down now, but to be honest I have no checked back in recently.
I took a bunch of photos of FOR RENT/FOR SALE sandwich boards, and tent-encampments. There were a lot of both.