and went through some growing pains. When we only had a couple of balls, we used aquariums, then moved to sweater boxes, then to a homemade rack and then to racks commercially made.
Aquariums with screen tops created humidity problems for us even here in Florida since we keep the snakes in our air conditioned house. We ended up covering most of the screen to keep the humidity in. I would think you might have the same problem with a sweater box if you cut out and put on a screen top.
A sweater box with a tight fitting lid with some small holes (we drill 3 or 4 on each side) cut at the top of the plastic box seems to work the best until you have several snakes and want to get or build a rack. We still use the old sweater boxes with holes when we get a new snake and put it in quarantine.
When you get to the point of needing/wanting a rack, think twice about building it yourself. If you have someone who is very handy building wood furniture it might be a snap, otherwise . . . We probably spent more in time and effort than a small one cost us.
Good luck in Janaury when you snake arrives!
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Alice Cobb
Florida Reptile Room