Rare opportunity in San Carlos to transform and expand an existing 1,605 SF home into a spectacular 2,685 SF custom residence. The sale includes fully approved plans for an approximately 1,080 SF addition, creating a modern farmhouse with 5 bedrooms and 4.5 bathrooms, including a junior ADU with private bedroom, bathroom, living area, and efficiency kitchen. The flexible floor plan is designed for modern family living. The main level offers 3 bedrooms and 2.5 bathrooms, including a primary suite on the same floor as the additional bedrooms ideal for families with young children. The lower level adds a second primary suite, providing long-term flexibility as needs change over time. Also on the lower level is the junior ADU, perfect for extended family, guests, an au pair, or a private work-from-home space. The approved design features open-concept living, designer finishes, and seamless indoor-outdoor flow to landscaped front and rear yards. Modern farmhouse architecture includes a white exterior, black-framed windows, and a black roof. An exceptional opportunity for an end-user or developer, with fully approved plans. Close escrow on a Wednesday, start building on a Thursday. Comparable new construction suggests a potential value exceeding $4M. Recent sale on Elm was $4.75M.