Today it's at 2091 S. Harvard Blvd. -- with the Santa Monica Freeway across the street -- but when it was built by James Cuzner of the Kerckhoff-Cuzner Mill and Lumber Company, it was at 1991 S. Harvard.
The Los Angeles County Assessor website says this house was built in 1904 and that the house next to it was built in 1905; since the lot next door looks empty, I'll say this is a c. 1904 photo (although there are cracks near that small 3rd floor window, and zooming in reveals what looks like recent repair work):
USC Digital Library --
http://digitallibrary.usc.edu/cdm/co...5/id/502/rec/2
GSV
More and better photos, plus history on the house (it's being restored after a bad fire) here:
http://www.flickr.com/photos/kansas_...n/11389207835/
An undated (c. 1930?) photo of Olvera Street, showing the Kerckhoff-Cuzner Mill and Lumber Company in the background at the NE corner of Alameda and Macy:
LAPL --
http://jpg1.lapl.org/pics17/00008486.jpg
1921 Baist Map:
Historicmapworks.com --
http://www.historicmapworks.com/Map/US/19411/Plate+005/