I would use deli cups the 8oz size work well.
I first saw them being used by Branden Osborne. I have since seen them being advertised by site selling supplies.
Anyway get the size you think you need and put a few small holes
around the deli cup or buy them already with holes in them from snake equipment suppliers. If you make your own holes you can drill them or melt them with small electric soldering iron ( be careful to not put too much tip through or the hole may be too big and snakes try to get out. You can also use a small hole punch 1/4 inch size I had to special order through Office Max but most office supply stores have or can get them. I do not recall price but it was under $3.00.
I then staple a small condiment cup 3/4 oz or 1 oz either size is OK to the inside of deli cup and then place a second condiment cup inside the first. The second small cup holds the water and I do not clean them when dirty just use a new one getting rid of old dirty one.
I first went to supermarket and got my first deli cups and they charged me 10 cents each and condiment cups were about 3 cents .
So with less than 15 cent you have nice small snake housing.
When large deli cup gets dirty you can clean them and reuse them or get new ones.
I have used both shoe boxes and the deli cups for young snakes and really like the deli cups best as feeding is super easy just drop in a pink and due to small area young snakes find food much eaiser and eat better than when in larger shoe box.
I use aspen bedding in the deli cups.
Ihave never lost a snake and its seems like I can see what
young snakes are doing better than when I used shoe boxes.
Plus they take up less shelf space.
When they outgrow the deli cups I then use the shoe boxes/