The Joint Archives of Holland has digital copies of the Sanborn Maps for West Michigan (these will be in black and white). Please contact Archives and Special Collections for access to the map you need. (archives@hope.edu). They have the maps for 1902, 1908, 1916, and 1925.
Color digital Sanborn maps for Ottawa and Alleghan Counties are also available from the Library of Congress from 1883-1899.