I would start off with a couple 600 watt lights then add more as needed....especially if this your first grow. You will make more mistakes...wait till you get everything dialed in before you invest tons of cash on many plants. You will get a pretty good yield off of 2-3 600W lights. I would go with 2 HPS 1 MH if you go 3....your light coverage will be much better than with the 1Ks...the lights may not heat your entire basement but I'm sure they will have no problem keeping the air around your plants warm....move em in until you get you desired temp and light footprint. You can always put up plastic that would trap the heat from the lights better than without.