For sure when you have a little tiny plant in a 3 gallon pot but.....When you have 12 of them averaging 10+ feet each , you can do it and then come tell us it's not that hard, They dont make tents that big, blankets are a no go unless you want fiber's and shit all over your buds and wood is fucking outrageous .... feel like mortgaging the house for a few 2x4's and some osb? Not being a dick because all of what you said it technically possible, but highly inconvenient and expensive, The only easy fix is planning ahead
OP.... Next year you need to do a little research on what strain would best suit you're needs in you're latitude so you dont have the same issue. You'll still get a harvest this season but more importantly you'll learn a valuable lesson for next year ... Last season I was in the same boat as you , I grew some cali orange and it didnt ripen till the beginning of November, I ended up hooking up hps lights and moved them into the garage to finish, was a major pain in the ass. Best of luck