I have a yearling coastal carpet right now. His new enclosure is being picked up Sunday, since he out grew the original.
Right now He is in 2x1x1 enclosure from JPM Reptilla.
For furnishings I have a sealed PVC Pyramid for him to climb, 2 hides, and water bowl. I'm using a UTH at the moment, but once he gets fully grown I'm going to switch to RHP, which I all ready have.
Now, for specific questions you had, it depends on what species of JCP you have. These are just generalized answers that will work across the board.
3x2x~2 should be big enough for most species as an adult, provided you give ample climbing room. Most are semi-arboreal.
You can divide, but the easier solution would be to get more hides. As long as they have plenty of hiding places to feel secure you should be good.
CHE, RHP and UTH are all good options. As a young snake, I prefer to use UTH. When they get bigger, RHP is what I like.
RHP's while more costly, are amazing. They are cool enough to touch where touch will not burn, but typically "blend" in with the enclosure. You want to mount them on the roof of the warm side, and run a goo t-stat with it. Ive used them for big boa's, retics, JCP's, ATB, GTP's and Boiga's.
Humidity in an AP style enclosure, or good sealed wooden (High Scale Enclosures
) is incredibly easy to do. I use a puppy ad as substrate right now just because its easier for me, and my humidity with just a small ball of water hovers around 45%-55% without doing anything other than keeping fresh water in there.
UTH and RHP are your best options.
Additional information you may need:
Young carpets are known to be nippy. Especially in the enclosures. Mine strikes when I open the enclosure 100% of the time. I have held him maybe 5 times. Once outside he is docile. Less handling leads to less stress and leads to a happier snake.
Look at the species you are getting. Irian Jaya's get to about 5 feet while Coastals can get to about 9 feet.
Your going to want a snake hook, if you dont have one. I would recomend a 30" one from Toby at Snake Charmer Hooks
. He is competitvely priced, does ship, accepts paypal and allows customization of his hooks.
Overall, my second favorite non hot species to work with. You wont be disappointed with them