I plan to eventually get a Bredli, and I'm trying to optimize my plan for minimal enclosure obsolescence. For my ball python this means using a cheap plastic container with a low ceiling until she's ready for a larger pvc enclosure, but I'm sure a Bredli will want more vertical space from the beginning. I could get a taller plastic storage bin, but I expect it's harder to manage ambient temps in taller bins with an external CHE. Opening from the side is probably more important for taller enclosures too.

Is there an upper recommended limit on enclosure size for babies/adolescents? Is starting with a 4x2x2 and eventually attaching another 4x2x2 (probably one horizontal, one vertical as I saw in another post on here) an appropriate plan? If 4x2x2 is likely to cause stress for a hatchling, what size should I look for instead?