Welcome to 403 Sumter Street, a beautifully renovated Charleston Single in the heart of Downtown Charleston's vibrant Westside neighborhood. Combining historic Charleston charm with modern convenience, this thoughtfully redesigned property offers approximately 1,870 square feet in the main residence plus a detached 338-square-foot guest cottage, providing approximately 2,208 square feet of total living space.Originally built in 1935 and extensively renovated down to the studs in 2021, this turnkey property features major system updates, including the roof, HVAC, water heaters, plumbing, electrical, and high-end interior finishes throughout.The main home offers a highly desirable and flexible floor plan with two potential primary suites - one on the main level and one upstairs - making it ideal for multigenerational living, guests, roommates, or evolving household needs. Each bedroom features its own ensuite bathroom and direct access to a private piazza, a signature Charleston architectural feature that adds both charm and functionality. The detached 338-square-foot cottage offers exceptional flexibility and value. Complete with its own full bathroom, kitchenette, and separate HVAC system, this space is perfect as a guest house, mother-in-law suite, private home office, long-term rental, or income-producing opportunity. Buyers interested in short-term rental (STR) potential should independently verify all requirements and regulations with the City of Charleston. Outside, enjoy a charming shared courtyard complete with café lighting, creating a warm and inviting space for entertaining or relaxing. The property also offers ample off-street parking for three or more vehicles - an uncommon and highly sought-after feature in Downtown Charleston. Ideally located just moments from Hampton Park, The Citadel, and Riverdog Stadium. You'll also enjoy easy access to some of Charleston's most beloved restaurants and coffee shops, including Leon's Oyster Shop, Melfi's, Huriyali, and The Daily. Upper King Street, MUSC, College of Charleston, shopping, dining, and entertainment are all just minutes away. Whether you're searching for a primary residence, multigenerational living arrangement, income-producing property, or downtown Charleston investment, 403 Sumter Street offers a rare combination of character, flexibility, location, and modern updates. Furnishings may be available with an acceptable offer, providing a potential turnkey opportunity for the next owner.