When you’re talking about harvest weight growing indoors this is typically qouted in size of canopy and not a per plant basis. You could grow 4 small plants and harvest roughly the same weight as one large plant, or lots of different scenarios. A pound of weed dry out of a 3x3 is attainable, but it’s not typical results from a new grower.
If you want a small grow with large capabilities at a budget friendly price I would go take a look at what @TheAbu95 does. Here a few links
I think it would be a lot to expect to repeat what he does, but certainly possible.