​Welcome to 10309 Grandhaven Avenue, an exquisitely upgraded colonial nestled in the highly sought-after Marlton South community of Upper Marlboro. This elegant home offers 5 bedrooms, a versatile den, two full kitchens, and 3.5 bathrooms, thoughtfully designed across a spacious, light-filled layout. The main level features 9-foot ceilings, beautiful oak hardwood floors, two bay windows, and an abundance of large windows that flood the home with natural light. It includes a formal dining room perfect for entertaining, a formal living room, and a large family room with 10 foot ceilings and a fireplace​ ideal for relaxing or hosting guests. A bright and airy morning room with two skylights offers tranquil views of the backyard and the serene golf course beyond, creating an ideal space to start your day. The gourmet kitchen is the heart of the home, showcasing ​​expansive cherry wood cabinets, granite countertops, a center island with gas cooktop, stainless steel appliances, a double oven, and a built-in wine cooler​ perfect for both everyday living and entertaining. The seller is the original owner and selected this premium lot, opting for every available upgrade, including a full brick fa​cade. Upstairs, the second level offers four spacious bedrooms and two full bathrooms. The luxurious Primary suite serves as a private retreat, featuring a sitting area, walk-in closet, and a spa-inspired en-suite bath. All bedrooms are enhanced with brand-new premium carpeting for added comfort. The expansive, fully finished walk-up basement is a standout feature, offering tile flooring throughout, a complete second kitchen, a separate entry, a bedroom, and a den​ providing exceptional flexibility for multigenerational living, guest accommodations, or potential rental income. Recent upgrades include a top-of-the-line Carrier Infinity HVAC system valued at $25,000 with smart thermostat and app thyat allows you to control your system from anywhere. and a newer architectural shingle roof installed just six years ago. The home also includes a two-car garage offering ample storage and convenience. Outdoor living is equally impressive, featuring a beautifully crafted quartz stone patio perfect for entertaining, a fully enclosed and active garden, and professionally landscaped grounds adorned with vibrant flowers, mature trees, and fruit trees​ creating a peaceful and picturesque backyard sanctuary. Backing to a golf course, this home provides stunning views, exceptional privacy, and a strong connection to nature. With high-end finishes, abundant natural light, timeless curb appeal, and a prime location close to shopping, dining, and commuter routes, this exceptional property offers the perfect blend of comfort, elegance, and convenience.