Simple enuff question but so many variables.

Are you wanting to go cheap or are you looking to maximize genetic expression?

TRUE FULL SPECTRUM CFL's only need be 5500K and can be found at medical light sites, like fullspectrumsolutions .dot. com

the crappy ones at wally world and hardwares stores...6500K and buy a whole lot of them. A whole lot.

A 4x4x2....could hold 8 of these big babies nicely and you would never need another light for veg.