A rare estate package opportunity in the gated community of Stirrup Key, this four-story Luxury Custom residence is offered with a separate vacant lot with its own Parcel ID, a transferable building right, and a deeded boat slip in the community marina. Together, these features provide flexibility for future expansion, an additional residence, or long-term value in one of Marathon's most established neighborhoods. The home offers elevated water views, water access, and a layout designed for both everyday living and entertaining. The ground level features a three-car garage, generous storage, and direct access to the pool, creating easy indoor-outdoor living. The second floor serves as the main living level with two bedrooms, two full baths, a full kitchen, and open living and dining areas that extend onto a large screened lanai, ideal for relaxed gatherings and evening breezes. The third floor offers a private primary suite, sitting area or fourth bedroom, with bar/kitchenette and fireplace. Primary suite bath offers spa-style features, and an expansive lanai with elevated views. A spiral staircase leads to the fourth-floor widow's walk, finished with travertine flooring and a water hookup. From here, panoramic views stretch across Marathon and toward the Gulf, offering a peaceful setting for sunrise and sunset. A private nature path winds through preserved surroundings and leads to a Gulf-front observation dock, ideal for wildlife viewing and enjoying the natural setting. Additional features include a lift to the second floor for added convenience. Located behind the airport with easy access to shopping, dining, and daily necessities, this property offers a rare combination of space, privacy, boating access via a deeded marina slip, and future development potential in the Florida Keys. Schedule a private showing to experience the space, views,& the value of the additional lot, transferable building right, and deeded marina slip in person. B&BATVAI