Barbara Corcoran has listed her celebrated Fifth Avenue penthouse — the property where she lived out her most personal real estate dream. The apartment, commanding unrivaled views of Central Park, was acquired by the entrepreneur in 2015 for $10 million, after a phone call from its previous owner finally surrendered a home Corcoran had coveted for more than two decades. The 4,600-square-foot duplex was comprehensively reimagined under Corcoran’s direction, with an additional $2 million invested in its transformation. Five bedrooms, five full bathrooms, and a wood-burning fireplace library speak to an interior shaped by a genuine passion for design and considered luxury. Now, with the need for more accessible living, Corcoran has brought the residence to market at $12 million — a price she considers fair, if modestly below the total invested.