Right on Bear Country! You gotta learn to crawl before you can walk and walk before you can run! This big of a grow requires the an expansive amount knowledge especially electrical power usually resulting in a subpanel or existing upgrade with a minimum of (4) dedicated 20 amp circuits and thats just a small tip of the iceburg!
Very good point. You are not going to run 6k watts without a properly set up electric system. You try to run that in in a regular house without modding the electrical you'll be just asking for trouble.
Don't take me or anyone else wrong. I don't think any of us are saying don't try to get there. Just you gotta work your way up, or have enough knowledge and other experiance to back it up if you want to succeed.
Room building aside, how you decide to grow in this area will have huge impacts on things too. Are you planning on growing several LARGE plants, a bunch of medium plants, or a TON of small plants. I grow a bunch of small plants(around 40 at a time) under my 1k light in a 4x4 tray. I have an ok size clone/veg room next to my flower room, and have another 25-40 plants going in there most of the time to feed my flower room as I harvest. If you're going to fill a 6kwatt room you will either need space to veg some Large plants for a long enough time, or enough space and a setup to veg enough medium or small plants as well.
If you were thinking a ton of small plants and just buying clones, you'd be looking at HUGE amounts of money which I think would be crazy. To fill a room like that you'd need HUNDREDS, emphasis on the "S". Basically I'm saying you need a veg room. It can be smaller then the flower room, but still needs to be big enough to feed it like I said. You can have less watts, and you can use non HID lights in there but still gotta have enough power properly set up to grow stuff.
SOoo maybe if you do tons of reading and really think you know your shit, and have enough other experiance do some floros and a 600 or 2 in veg for the mothers, clones, and vegging plants. Then 2-4 more 600s or 1ks for the flower room. The bigger you go the more cooling you need, and the bigger your fans have to be. My 1k is cooled by a 6 inch fan, and it works OK, not great. 1k lights really should have 8 inch cooling I think.