In an August 1981 entry in his now-published diary, Andy Warhol wrote: “It's a beautiful building, but buying it would be like buying a beautiful piece of art… I could put in hot air and toilets and it would be an artist's space.” The building he was talking about was 158 Madison Avenue in New York City, a former Consolidated Edison sub-station that became the pop artist's studio, soundstage and offices for Interview magazine. Largely considered to be the fourth incarnation of “The Factory,” two of its more famous predecessors being located at 33 Union Square West and on East 47th Street, Warhol nevertheless used the building from the time he bought it in the early 1980s until his death in 1987. Fueled by New York's white-hot residential market, the former artist's studio is now slated for redevelopment into luxury condominiums. The developer on the project is Thorwood Real Estate, a partnership betweenButtonwood Real Estate founder Andrew Heiberger andThor Equities chief Joseph Sitt. The group reportedly plans to spend $100 million to turn the T-shaped, four-floor building into a 22-story project with 50 luxury loft condos. In hindsight, Warhol himself seems to have been a rather shrewd real estate investor himself. Eothen, a 5.6-acre, seafront compound in Montauk, Long Island that he once owned with partner Paul Morrissey, is currently on the market for approximately $50 million.