I would be running double ended 1k's for sure. Dont get hung up on gavitas, there built in china now just like all the other brands. If you can get better prices on other quality brands go for it. Since you dont need a separate veg or dry room, then you would want to at least have a separate area where you'll have your electrical, reservoirs and general work space. Easiest would be building a full length wall 30', then your flower room would be 30 square granted you made your entry, electrical, reservoir and work room 10'x30'. 30x30 you could run 36 lights, 2 plants per light on rolling tables with trellis. I would suggest coco or a coco mix in 10-15 gallon pots on a dtw drip system. Depending on your climate 15-20 tons of ac should do it.