50 grams fresh will probably give you about 12 dried, depending on several factors but for a ballpark estimate divide by 4. 12/12 from seed to harvest is all ive done for the past four years, out of necessity, and I can assure you you will waste your time going with autos at 12/12. The main benefit to autos is being able to get multiple crops outdoors, or to get an early harvest outdoors or in places with a very short outdoor season. Autos indoors just doesn't make sense, it's at least 50% more power consumption to get the same or less yield. Autos have their place and are really good for use outside Imo.
here's one that's gone 12/12 from seed in dwc with 600w hps, keep in mind i cut almost two ozs off it at day 70, and haven't defoliated it other than that since birth, besides two leaves that were touching the wall and molding. Also this is a cookies cross, which is a famously mid yielder ive read, girl scout cookies, not this cross.