I would imagine CAR derives that statistic from the names on the RPA. If the names are different then they call that friends or co-workers. That may or may not be true. I have had couples that are not married share a home. So again, I would view that stat with skepticism. Also I know of some speculation purchases that were made with multiple names on the RPA. The one concrete example are two guys who bought a home in Normal Heights for the mid 400s and asked me to list the home. After renovating it thoroughly then needed 530k to break even. The sad thing was when they bought the place the market was in the tank but the Realtor they used assurred them they would make a killing. Well they called her after they renovated and she said that the market took a sudden unforseen turn but by the summer it would be back full steam. Anyways they got killed on the home. Rather then take the cash loss one guy sold his primary home, lost all his equity, and bought out the other guy. Now instead of living in his nice 4/3 home in Alpine he gets to live in a 2/1 in Normal Heights.