File under historic artifacts not worth buying: 1842 18th Avenue. According to the listing, once the home of Commodore Perry. Most people associate "Commodore Perry" with the American naval officer Matthew Perry, who in 1853 induced the Japanese to open up trade with the United States. But since that Commodore Perry died in 1858, we're seriously doubting the provenance. Besides, Commodore is a naval rank and the Presidio's always been an army base. Commodore Perry did have a verifiable pied-à-terre at the Admiral's Row at the Brooklyn Navy Yard when he wasn't off swashing his buckle in the service of American expansion before the Civil War.
Whatever. The house is clearly early-twentieth century, and the two dates cited in the listing, 1915 and 1923, are probably the dates it was constructed and was subsequently moved to the current site. It certainly could have been officer's quarters, built in the Presidio and moved down 19th Avenue in 1923 to the Sunset, however unaided by any commodores. One of the most unsympathetic renovations we've seen in while, including what appears to be a dry moat masquerading as a patio. New on the market and commodore-ing $1.738M.
[Update: We thank the commenter PvP who sent this link to General Pershing and the tragic fire that killed most of his family. The realtor has changed the listing to reference "Commodore Pershing". Based on the photo of the burned-out shell of a Victorian house (scroll down the link) perhaps the listing should read "constructed from building materials from General Pershing's home in the Presidio".]
· 1842 18th Avenue [Redfin]
· Matthew C. Perry [Wikipedia]
· Admiral's Row Demolition [NYTimes]