If you get one that shows pistils early, like say 12-15days, you'll be lucky to get an one oz, they stay small.
But 2-4ozs, a plant, is about average, imo, I'm no expert at all, the most I ever got from an auto was a couple of grams short of 8ozs, dry. A Northern Lights auto from Nirvana.
Some people get way more than that, on here, but I aint, ,I'm happy to get 2-4 ozs, from one.
What I'd advise, is to get seeds from a good
place, then ever now and again, your still gonna get one that don't want to grow good and healthy.
HappyGrowing