your getting a GDP of kush for $100? At any rate, I think you are vastly underestimating the cost and value of the product... you must be a patient in Oregon LMFAO. Any product has a production and distribution cost. In addition, the free market dictates that higher quality products fetch higher prices as they are in higher demand and there is less of them.
So in terms of cost inputs you need to add the following to your list:
There are start up costs:
lights
ballasts
ducting
fans
air conditioners
controllers
co2 dispensers
containers--lots of them for you soil types
watering and spraying utensils
ph and ppm meters
hand lenses
shop vac
hoses and fittings (for you hydro guys)
RO water filtration system
air pumps, water pumps, air stones, etc
dehumidifier
dixie cups, cloning light, warming trays, humidity dome...all that $10-$20 shit that adds up.
To a newb growing 2 plants in a tent it would seem like overkill but someone growing 12+ large plants with high quality results will be shaking their head uh huh, uh huh. My 4k watt grow room = $7,000
Then there are fixed costs: ergo.. how much power does it take to RUN all that gear.
If your running 4k or more watts in a sealed room then you have at least another 2k watts (if not more) in fans, AC, dehumidifiers, pumps, etc.
Now there are the variable costs: in this case I look at consumables..ie you use them and its done.
Soil and or other substrate
cloning gel
nutrients.. and nutrients are fucking EXPENSIVE. Go buy 6 months worth of quality nutrients for a 75 gallon rez..your in the $500 range.
And finally.... MY TIME. I don't grow weed because I need to not have any free time in my life. Growing buds, allot of them, is almost a full time job, at least 20 hours a week. Those without lots of plants don't realize how long it takes to clone, trim, train, mix nutes, monitor conditions, harvest, trim, dry, weigh, bag, etc etc etc. Good growers possess a specific skill set, and those skills have a monetary value. Just like anything else. You want a cheap ass lawyer out of the yellow pages or the best guy in the city charging $300 an hour. I have tried both, trust me, you want the latter.
So yeah, $3.50 a gram is a pretty much bulllshit figure.