You need a ballast for each light. 3 ballast 3 lights 2 ballasts 2 lights. You can get each ballast at an electrical supply for 40 to 50 dollars. Then all you need is, wire nuts, grommets, sockets, switches, a box to mount them in and wire, O yea and tools. You also need to be able to reed a schematic. I made my own 4x175 watt light set up this way and total cost was under $300.00.