I think to first determine how many plants you should grow, ask yourself how much bud you’d like to have, or how much you normally use. Are you growing it just for you or do you intend to sell it (which is obviously risky)?

I’ve only done one grow. It was three autoflowers, I provided only water (and lights), no nutrients or low stress training, and I was gone for an entire month during the grow lol. I had friends “check in on them” while I was gone but they didn’t do a great job… two of them were basically dead when I got back. So out of essentially “~1.5” plants I still got 2.5oz, again, on my first grow where I did not do many things that I could’ve/should’ve done.

I don’t smoke all that much, but 24-50 plants per year should give you several pounds of weed, and that’s only assuming 1oz per plant. If I were you I’d start off with 2-4 plants and see how it goes, but that’s just me.