Just a couple of things to ponder...

Is this going to be a veg-only room? If not, you'll have to divide the room in two. One side for veg, one for flower. This will be a major headache, mainly because of heat, light leaks and ventilation.
Were it me, I'd pick a smaller closet for veg, and set this one up as a flower room. Or, you can use this room and go from seedling to harvest, and all you'd really need to change is the lights when it's time to switch from 18/6 to 12/12.

Those spotlights run at around 10,000 degrees f. Ineffecient, to say the least. You'll spend big bucks cooling the space back to within acceptable ranges. Put the light in the empty closet and turn it on for a couple of hours, and see how the closet handles the heat. I'd start looking for alternative light sources now. If you want a parts list...there are plenty of growlogs you can look at to see what other's are having success with. :jointsmile:

Stealth from someone outside the house, or from within...?