Just completed by boutique custom builder Heartwood Corp, this 7-bedroom, 9-bathroom, 9,600-square-foot Water Mill South estate showcases signature craftsmanship and refined detail. Positioned on prestigious Cobb Road behind a motorized gate and enveloped by mature, professionally designed landscaping, the property offers a private retreat moments from Flying Point Beach and Southampton Village. A soaring two-story foyer introduces the open, light-filled layout, highlighted by architectural floor-to-ceiling millwork on a double-sided gas fireplace shared with the living room. The dining area flows into a fully outfitted butler's pantry with sink, ice maker, wine refrigerator, and walk-in pantry. The chef's kitchen blends elegance and performance with custom white oak and painted cabinetry, integrated luxury appliances, and a hybrid waterfall island ideal for entertaining. The first-floor junior suite features a private patio, two walk-in closets, and a large spa-inspired bath with double vanity and privacy-glass shower enclosure that welcomes natural light. The living room, kitchen, foyer, and junior suite all overlook the landscaped grounds and pool, creating seamless indoor-outdoor living. A mudroom with garage access and a powder room complete the main level. Upstairs, the primary suite is a tranquil sanctuary offering two walk-in closets, a luxurious bath with soaking tub, separate vanities, makeup station, and privacy-glass shower and water closet, plus a dedicated office and serene views. Four additional ensuite bedrooms, a bonus room, and a custom-outfitted laundry room complete the second floor. The lower level is designed for recreation, featuring a glass-enclosed wine cellar, den with wet bar and wine cooler, flexible gym/media/game space with exterior access, a private sauna with Bluetooth controls, a full bath with steam shower, powder room, and two guest or staff bedrooms. Outdoors, resort-style amenities include a heated saltwater Gunite pool with integrated spa and sundeck, outdoor shower, stainless-steel kitchen and bar, and a dedicated outdoor powder room for poolside convenience. Expansive patios and lush landscaping set the atmosphere for effortless summer living. With Wi-Fi-enabled smart-home capabilities, custom cabinetry, tailored closet systems, central vacuum, laundry on two levels, and a radiant-heated two-car garage, 158 Cobb Road embodies timeless sophistication, abundant natural light, and modern Hamptons craftsmanship.