Cheap/Makeshift Grow Tent?

I'm looking to grow in my basement so that I have sufficient space for a bid ol ScrOG, designing a large box for maybe 12 plants, to start. The basement has some heating but it's pretty cold and humid. Is there a proven method or a cheap product I could use to basically cordon off the environment of the basement from that of my crop? Keep in mind that I'm buddin on a budget here.

i have a hydrohut mini fram and a hydrohut original skin that would work i woule sell all of it or 60$ it fits but a little baggy/big but a cheap grow room.. i have shit loads of stuff
da plantDOC