A little container, tubaware can be used for the frog, just poke some holes in it, or melt them in it with a needle.

Pillow cases can be used for your snakes, and that kritter keeper if big enough can be used for the bearded.

The 20 gal tank you say that ball python is in, is way to small btw. I have my 2 1/2 ft, almost 3 foot anaconda in a 30 gal long, and I will have to get her a bigger tank come november. She is about as long as the tank. So I know that 20 gal tank can't be big enough, but i'm sure you'll fix that with time.