how much room should i have?

I am planning to make a small grow box for every individual plant I have and would like to know how much space (preferably in sqft) I should have for each plant to grow properly . (note I have prepared for all entities accept space) I mostly need a minimum or maximum to work off of, but an estimation would be fine.

The answer I was taught in management school is "it depends more information is needed". What that means is what are your goals with the plants? If you want to grow them 12" high in veg state then switch to flower after 4 weeks and let them bud for 2 months increasing height another 24" that's 36" but then what is your light fixture (CFL, T5's, MH, HPS?) you are using as this will add both the fixtures depth and distance from the plants. Therefore the correct answer based upon what you posted is a variation of the old fishing tale by the one armed country boy, "that fish was this long he said holding up his one arm."