600w HPS, 630w of CMH, or high quality COBs. HPS, serious density...CMH, serious frost, COB, serious efficiency and terps. HPS high heat, CMH med heat, COB low heat. HPS cheapest to setup. COB/CMH a little pricier to setup, less bulb maint.
HPS, need a vented hood and I use an Active Air 440 CFM fan, with speed controller. I use Blizzard Oscillating Fans but Comfort Zone clip fans might work, and in the winter, get an ultrasonic humidifier. 6" Carbon filter.
CMH is open hood, just vent the tent.
COB you may need to vent, but prob on low low.
Depending on location and time of year, AC and or Dehumidifier may be necessary in the area of the tent.
Good luck, I'm trying out CMH personally, but have grown HPS.