Positioned in the heart of McHenry, Illinois, 4119 W Shamrock Lane presents a rare opportunity to acquire a fully built-out, 16,500 RSF professional medical office building. Constructed in 2003 and meticulously maintained, this two-story asset comprises seven office condominium units—offered together as a 100% building sale. The first floor is fully leased to established medical tenants, providing immediate in-place income. A 4,781 RSF suite on the second floor is currently vacant, with the potential to expand to approximately 8,500 RSF, making it an ideal scenario for an owner-user seeking occupancy with upside. The building features elevator access, ample patient parking, and recently renovated lobbies and common area restrooms (2020), enhancing the overall tenant and visitor experience. Located just one block south of Northwestern Medicine McHenry Hospital, the property benefits from strong medical synergy and visibility along Route 31, with updated signage opportunities available. As part of a three-building association, the property enjoys shared infrastructure and a professional environment conducive to healthcare and office users. This offering is well-suited for investors seeking stable cash flow with value-add potential or medical professionals looking to establish a flagship presence in a growing healthcare corridor. The surrounding area is a mix of residential neighborhoods and commercial services, with excellent access to major thoroughfares and a strong local demographic base.