Legal multifamily duplex in Mount Vernon, NY paired with an adjacent buildable lot — a rare Westchester County investment package offered together for the first time. 120 South 11th Avenue is a three-level, multi-unit duplex offering approximately 4 bedrooms and 3 full bathrooms across the main house plus a finished basement level — with multiple kitchens, separate living areas, and private entrances throughout, ideal for owner-occupancy with rental income, a two-unit rental, or a multi-generational living setup. First Floor: Eat-in kitchen, full bath, combined dining and living area with charming bay windows, and a private bedroom accessed through its own separate entrance. Second Floor: Bright and spacious layout featuring a primary bedroom, second bedroom, separate living room, formal dining room, eat-in kitchen, and full bath — plus a versatile bonus room with private access above, perfect for a home office, guest space, or extra storage. Finished Basement: Large additional bedroom, dedicated utility/laundry room, and full bath — excellent for flexible living space. Sold together with 116 South 11th Avenue, an adjacent residential land parcel, this package delivers a income-producing multifamily property plus additional land in a single transaction — offering upside for expansion, parking, future development, or long-term investment growth in Mount Vernon, Westchester County.