For sativa's keep it tall...like to the roof.that exaust fan will work great with a carbon filter...without one it is stronger then you need,but it can never be too strong(you want the fan to replace the air within 5 minutes)
Flower with 1000w HPS and veg with 400-600 MH.Get some floro's for the seedling's.Sprouting under HID's is not for beginners...I'm doing it mas we speak and it's a bitch.
So make your room at least 6x6 and all the way to the roof.

If you want to just ask me anything ,just pm me(personal message through this forum) :thumbsup: