The Kaufman family’s Sage Realty is selling the 40-story office tower at 767 Third Avenue, now about 50% vacant, for around $100 million. Originally built in 1981, the building underwent a $30 million renovation completed last summer, but the leasing market struggled post-renovation. Sage Realty hired Eastdil Secured to manage the sale. Options for new owners include leasing the vacant space or converting it to residential use. The building, overseen by Jonathan Kaufman Iger, is in a challenging market, with Third Avenue office vacancies at around 20% due to the shift to hybrid work.