three 100 year old streetcars were found in El Cajon, still existing as a residence, pushed together like a triple wide trailer house... and found in the late 1990s, but rescued and potentially going to get back on the San Diego tracks as moving historical monuments!

this is the best preserved of the 3, and if you want to see an example of what streetcars made into a home look like : http://justacarguy.blogspot.com/2009/09/street-cars-getting-second-life-as-home.html or

  this development was on the corner of India and Laurel. A facebook post https://www.facebook.com/photo.php?fbid=428651380501679 had one comment that tells of a couple that were rented out 40 years ago in a backyard on Oregon st

and the 2 that I know of that are still existing as homes, and one as a restaurant/diner http://justacarguy.blogspot.com/2008/06/survivors-of-era-i-doubt-anyone-else.html

http://www.sandiegohistoricstreetcars.org/