Potrero Hill Duplex with Double Upside! This well-maintained 1987-built building is far more than meets the eye: two solid tenant-occupied units PLUS the opportunity to build out an enormous bonus space below for a 3rd and potentially 4th unit! Perched on a Potrero slope, the property delivers two generous 2BR/2BA units with good rents and a clean operating history. Updated plumbing and electrical throughout means you're buying a building that's been cared for, not deferred. The seller will deliver an approved set of plans for a studio apartment - ready to reactivate the permits! This is a rare head start on ADU development in a city where entitlements are everything. For an owner-occupant buyer, this is a compelling path: build out the studio, move in, and let the two upper units cover the mortgage. And below that, a spacious garden-level room awaits your architect and imagination: a second ADU, a home office, creative studio,flex space, or perhaps expand the existing plans into this space. The bones and the square footage are there - you bring the vision. Each unit is bright and east-facing, with a thoughtful layout. The primary bedroom features an en-suite bathroom, while the hallway bathroom connects to the second bedroom. The sunny backyard and deck adds charm to an investment property and awaits your green thumb. This prime location delivers on every front. The cafes, restaurants, and groceries of 20th Street & the 18th St corridor are just a short walk away - plus Ikon Coffee is on the corner! A short stroll to Dogpatch, Caltrain and the Muni T-line. Quick access to the 101 and 280. Wow! Whether you're an investor seeking stable cash flow with a clear value-add path, or an owner-occupant ready to build your own unit and let the rental income do the heavy lifting, this property offers a rare combination of income today and upside tomorrow. Don't miss!