Newspapers can be a great resource. The Everett Public Library has copies of the Everett Herald, Everett Morning Tribune, Monroe Monitor, Stanwood Tidings, Snohomish EYE, and the Northern Star. Unfortunately indexing is limited and often non-existent. Computer indexing began for the Herald in 1992, and while the Everett Public Library indexed the Herald from 1971 through 1991, articles are listed by subject and not easily searchable.
If the property is on the National Register, news items may be indicated in the application bibliography. If you know approximate dates, sometimes events such as a house moving, fires, and remodeling may have made the news, especially in the small community newspapers. Additionally, the Washington State Library has a large collection of state newspapers, many of which have been digitized.
Pictures of street views, buildings, neighborhoods, and residences may be available in the Northwest History Room. Some of the local historical societies may also have photograph collections. Often past residents, neighbors, or people associated with a particular property will have old photos of the place as well.