Buying used certainly allows for more options. If this were me, I'd section-off a ~4.5-5 x 12' area and run 3 x 1K. Galaxy/Quantum ballasts, Sunlight SSII or Blockbuster reflectors, $35 Sylvania lamps. Reflectors on a closed loop with a 6" centrifugal, and the room vented with a 8" centrifugal. 3X8" pipes/ducts as intakes. Pro-Mix, Jack's Classic fertilizer, $3 2gal (10") pots from Walmart.