Marken Gjestehus offer 2-, 3-, 4- and 6-8 bed rooms. The 2-bed rooms may be used by a single person. Jakob's Apartments offer single or double apartments and dormitory. Bergen YMCA hostel offer 2-, 4- and 6 bed rooms, and dormitory. All of these are nice and located centrally in Bergen, walking to Vil Vite should take you about 20 minutes. Montana vandrerhjem is another option, but farther from town - you will depend on bus.
City bus schedule and stops can me downloaded from here