The best way to grow is ALONE and don't ever tell anyone you are growing.
Secondly grow a couple of plants all the way through to harvest just to see if you are able to do it. Not everyone has a green thumb.
I'm not sure that there is a way to grow 100 plants economically.. What kind of space are we talking about here?
misshester is right. "partners in crime" almost never work. Sure YOU may not say anything to anyone, but can you be 100% certain about your partner? NO! And if shit hits the fan, they'll give you up. It's 99.999% certain. It's all well and good to talk about "brotherhood" and best friends for life, but when that best friend is looking at 5 years (the DA will probably scare him with 50 years) that MF
will roll. Looking at time does strange things to people.
How can you do 100 plants economically? Economically is a relative term. Figuring a 1/2 # per, that's around $240,000 in my neck of the woods. If you spend $75,000 on equipment (assuming you have a safe place to grow lined up) I'd say that its pretty economical. Not many businesses turn 130,000 the first year.
You are getting into territory where the weight and amounts of money can turn ugly. People get killed for alot less. dealing with that kind of weight, you'd better be carrying a gun, know how to use it, and be ready to do so. There are all sorts of nasty folks out there who will try and rob you, jack your grow, etc and you are gonna have to defend yourself. If you don't, things will probably go south real quick.
Also, like any large business, you're gonna need a legal dept. Figure another $30,000 for a bondsman and an attorney retainer, plus a decent stash of cash for emergencies.
But....that being said, lights can be had for cheap. There really aint no way to "cut" electric costs. 1000 KW/Hrs is what it is. HID lights are the most efficient lumens per watt. If you are going for being known for quality, don't cheap out. For the most part, you get what you pay for.
It's a great dream, but do yourself a favor and keep it that way. If you're hell bent on a commercial grow, do 50 plants solo. Same bank, fewer people in the security equation.You're still talking amounts of money and weight that
will attract the attention of some not so nice people.You ain't sellin' yer buddy an OZ any more, you're getting into the big boys game now.