Just as food for thought, a constrictors NW 4' x 2' x 14" cage weighs around 50 lbs and an animal plastics T-10 cage with sliding glass doors is probably around 60-65 lbs empty. The cages you are proposing with substrate I would guess would be well over 100 lbs.
I weighed one of my exo-terra cages once (18" x 18" x 24") with substrate and decor, it was like 70 lbs.