I am obliged to go with the 6", as I simply cannot risk it. I was considering doing some jack herrer autos outside, but given what you said that has definitely put the nail in the coffin for that idea. I think I might start with a 2x2 and then upgrade if I really branch out and look to grow more. At the moment, I am really thinking 1 plant at a time to keep smell, upfront and overheads to a low. If that goes well, I can easily afford another $100 tent to upgrade.If you are up for a bit of DIY wiring, standard LED bulbs can grow some very nice weed for something like 1/2 the price of commercial lights. The difference may even be bigger down there after duties and the like are factored in.
I would definitely go for a 2x4 tent rather than a 2x2, especially as you intend to help family and friends. You would be able to play around more for strains for different purposes with the extra space. Also, height is your friend. Don't buy a short tent. I would not go less than 6 feet myself, and the diy I built is over seven.
Re. stealth, you really need to be on top of the smell issue. I would go with 6" if I were you, and choose a carbon filter that has been well reviewed by experienced growers. Once you discover a smell problem, you may already be too late, and it will be a bugger to fix quickly. Don't even think of trying a grow outside on your property. Even strains with reputations for low smell are not no smell, and they regularly turn out to be different than reputation suggests (my current Northern Lights is high on the stealth list, but was way too smelly to not notice outdoors).
And one other thing given the consequences of your being found out. Tell no one, no one, that you are growing. If you can't keep your gob shut, do you really think others will be able to? If you supply some to friends, just tell them that you have some that a friend gave to you on promise of not saying anything. Even here in Canada where what I am growing is perfectly legal, I am very careful about who knows what I am up to. The issue for you is not just the local law however serious that risk is, it is also the local teenage stoners who will steal your stuff and be happily waiting for the next grow. Once the word is out in the wrong crowd, you could be buggered permanently, law or no.
Good luck with your grow mate.
Silence is golden. Thanks for much for your guidance and time, I really appreciate you helping me. Seriously, thank you.