Lights: 400 watt hps digital ballast. $98 From ebay Soil: Peat, Perlite, EWC, kelp meal, garden lime, and granite rock dust.(let sit for 4 weeks before use.)less than $100 sourced from various places. Air circulation: If there is no window A/C unit i would recommend leaving your rooms door open while a fan rotates the air and if there's a screen in your window i would recommend having it open if possible. New fan if needed. $20 box fan will do. Walmart As for keeping your room "light tight" you should decide for yourself before giving your plants a night time if the area will keep the light out during a night cycle. Emergency blankets work just fine attached to tarps to make them easier to manage as well as less see through. $70 should get you enough emergency blankets and tarps plus a $20 staple gun with staples.(You can get either or but id recommend both.) Walmart. This is pretty much my grow room minus some things i got before i knew i would not need them. Save yourselves some money. ( If this seems too expensive just replace hps with cfl and buy 2 bags of soil. One for veg and one for flower. One to veg in and one to flower in after transplant to flowering pot. If you dont plan to transplant at all just use a big enough bucket/pot/smart pot to start off in so that you will be sure to have enough soil nutrients for the duration of the grow.)