Single-family giants are selling houses they bought amid the Housing Bust and shifted to new construction of build-to-rent developments. Multifamily caught up in CRE turbulence. The top six single-family rental landlords own 422,000 single-family properties; the top six multifamily landlords own 660,000 rental apartments; and mom-and-pop landlords own 11 million single-family rentals, out of nearly 50 million total rental units.Big multifamily landlords and mom-and-pop single-family landlords are classic el ...