THIS $26.5 million five-bedroom landmarked townhouse at 74 Bank St. was once home to artist George Condo. Now the 6,000-square-foot home, which has two fireplaces, is being marketed as a single-family mansion. Built in 1842, the residence has been redone by top architects Leroy Street Studio (LSS) and Christina Markatos Design. The home comes with 13-foot ceilings, a large formal dining room, living room and landscaped garden. The listing broker is Jim St. Andre of CORE.