If you're looking for a low cost, high intensity, low heat output lighting system, take a few minutes and look over what Terpene has been doing with screw in LED light bulbs..
Even his simple set up was more work than I wanted to do so I just got a 4 ft power strip, some plug in sockets and an 8 pack of 8.5W LED bulbs (HD, i think they were $13 for the pack). My total cost for one strip was about $50. The light out put at 18 inches is the same as my 630 CMH has at 4 feet. No heat build up at all.
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get two or three of those strips to light a 4x4 area. Your biggest issues will be: is this too much light? and what to do with all the money you didn't spent on the fancy pants lighting set ups and electricity bill
Best of luck with your grow!
Ona