Multiple houses in my area (Southern California) have recently redone their garage to be full, two story units replete with external staircases... all but one of which is accessible from the street!

They are budget ‘apartments’ going up in standard tract housing from the 1950s with the original houses being 900-1,000 square feet. They are boxy, glaring eyesores that are just a fancy excuse to extort more money out of the desperate.