Welcome to a true architectural Luxury masterpiece in the heart of Fountain Valley. This rare 2026 custom-built estate offers two brand-new houses on a single lot, totaling over 4,500 SQFT of meticulously designed living space. Perfectly positioned in a premier school district, this smart-home sanctuary is just steps from the lush greens of Mile Square Park and local golf courses, while remaining minutes away from the cultural hub of Bolsa's Phuoc Loc Tho and the iconic sands of Huntington Beach. With fully paid-off solar, separate addresses, and independent utilities for both units, this property defines modern luxury and multi-generational flexibility. The main residence is a showstopper, boasting Appx 3,760 SQFT of sophisticated design. Beyond the custom double-door entry, you are greeted by soaring ceilings, an electric fireplace, and a designer loggia that seamlessly blends indoor and outdoor living. The chef's kitchen is a culinary dream, featuring a waterfall granite island, Thermador professional appliances, and sleek white cabinetry extending to the ceiling. The main floor is thoughtfully laid out with a private office, a dedicated yoga room, and a guest bedroom-each featuring its own en-suite bathroom-ensuring every family member enjoys ultimate privacy and convenience. Upstairs, the home continues to impress with a massive loft family room designed for high-end entertainment. Two additional bedrooms and bathrooms accompany the palatial primary suite, which serves as a true sanctuary with its own private balcony overlooking the picturesque streetscape. The primary bath offers a spa-like experience with a separate soaking tub and walk-in shower. Technology is integrated into every corner; from the three-car epoxy-floored garage to the motorized blinds, recessed lighting, and smart TVs, the entire estate is controlled via phone application or Alexa for effortless living. A detached Appx 747 SQFT ADU that mirrors the main home's luxury. This secondary residence with soaring ceilings includes a full kitchen with an island, 2 spacious bedrooms, 2 bathrooms, and its own laundry area, all kept comfortable by a dedicated mini-split HVAC system. The exterior is professionally landscaped with decorative spotlights and vibrant flora, creating a resort-like ambiance at night. Looking for an income-producing asset or a compound for a large family? This 2026 masterpiece is a once-in-a-lifetime opportunity to own the finest craftsmanship in Fountain Valley, CA.