[Speed of green]

i have 5200sf of greenhouse for flower and 1500sf for veg-- this will largely depend on your growing method.

I am in a warm climate that has many days of sunshine a year, for my supplemental lighting i use a 15w phillips bulb over each plant.

if you live somewhere cloudy you may need to use a stronger supplemental light (gavita)

[MedicineTrees]

As far as the physical structure itself is concerned, it MAY be more cost effective to adapt something like a non-greenhouse specific design like Versatube, skin it with your choice of plastics, etc. and outfit accordingly.

https://www.versatube.com/