The listing calls this building at 799 Washington Street “one of the last grand historic structures in prime meatpacking district.” And it could be yours for a cool $75 million. Turning it into a mega-mansion, however, will require serious work. (Though there’s no lack for inspiration when it comes to mega-mansions in New York.) The 23,000-square-foot structure is currently configured as a high-end film studio and commercial space, topped off with a residential penthouse unit. Other suggestions to any deep-pocketed buyer, per the listing, include conversions to a boutique hotel or a multi-unit, live/work building.