while also breaking in new personnel. By 1927–28, at the end of the silent era, the production cost of an average feature from Hollywood's major film studios had soared, ranging from $190,000 at Fox to $275,000 at MGM. These averages, again, reflected "specials" and "superspecials" that might cost as much as $1 million and films made quickly for around $50,000. Some studios, like large Paramount and growing Warner Bros., depended on block booking and blind bidding practices, under which "independent ('unaffiliated') theater owners were forced to take large numbers of the studio's pictures sight unseen. Those studios could then parcel out second-rate product along with A-class features and star vehicles, which made both production and distribution operations more economical." Studios in the minor leagues of the industry, such as Columbia Pictures and Film Booking Offices of America (FBO), focused on low-budget productions; most of their movies, with relatively short running times, targeted theaters that had to economize on rental and operating costs—particularly those in small towns and so-called neighborhood venues, or "nabes," in big cities. Even smaller outfits—the sort typical of Hollywood's so-called Poverty Row—made films whose production costs might run as low as $3,000, seeking a profit through whatever bookings they could pick up in the gaps left by the larger concerns. With the widespread arrival of sound film in American theaters in 1929, many independent exhibitors began dropping the then-dominant presentation model, which involved live acts and a broad variety of shorts before a single featured film. A new programming scheme developed that would soon become standard practice: a newsreel, a short and/or a serial, and a cartoon, followed by a double feature. The second feature, which actually screened before the main event, cost the exhibitor less per minute than the equivalent running time in shorts. The majors' comprehensive booking policy, which would become known as the run-zone-clearance system, inadvertently pushed independent theaters toward adopting the double-feature format. As described by historian Thomas Schatz, the system "sent a picture, after playing in the lucrative first-run arena, through the 16,000 'subsequent-run' movie houses; 'clearance' refers to the amount of time between runs, and 'zone' refers to the specific areas in which a film played. Typically, a top feature would play in its second run in smaller downtown theaters [many major-affiliated] and then move steadily outward from the urban centers to the suburbs, then to smaller cities and towns, and