Rarely does an opportunity like this come along in one of Marin's most beloved neighborhoods. Ideally located along Mill Valley's vibrant Miller Avenue corridor, this beautifully updated and fully vacant two-unit property offers an exceptional blend of flexibility, comfort, and convenience ideal for owner-users, extended families, investors, or those seeking supplemental income potential. Just moments from downtown Mill Valley, Highway 101, award-winning schools, shops, restaurants, cafs, and endless hiking and biking trails, the location offers the very best of connected Marin living. The upper residence features a light-filled 3-bedroom, 2-bathroom layout with open living spaces, updated finishes, and a warm, welcoming feel throughout. Off the main living area, a private outdoor patio and yard space create the perfect setting for entertaining, relaxing, gardening, or enjoying indoor-outdoor living. The lower 1-bedroom, 1-bathroom residence is thoughtfully renovated and offers incredible versatility ideal for rental income, guests, extended family, a private home office, or creative space. Both residences have been extensively updated with remodeled kitchens and bathrooms, hardwood floors, updated appliances, quality cabinetry, and in-unit laundry. Additional improvements include a newer roof, redwood deck, retaining walls, seismic retrofit work, and fire sprinkler system. A spacious garage provides excellent storage and utility space. Whether you choose to live in one residence and rent the other, create a multigenerational living arrangement, or simply enjoy the flexibility of having two beautifully updated homes on one property, 288-290 Miller Avenue presents a rare Mill Valley opportunity in an exceptionally convenient and desirable location.