I've had my 3.5mo-old pineapple GCC for almost a week and we use this cage:
https://www.amazon.com/Prevue-Products-Wrought-Hammertone-3151BLK/dp/B000FRV3M2/
The space is adequate, and for now she spends most of her time inside. I'm working to transition her into exiting the cage more often with apartment tours every few hours to pique her curiosity.
This is the cage as of this morning:
Three perches, three toys, cuttlebone and beak stone above the food and water bowls. Space is adequate like I said, but seems a little crowded. In particular she exercises every few hours by rapidly flapping her wings in place, and I can tell she's cautious about hitting anything that's in the cage when she does this.
I believe the next size Prevue cage (24 x 20 x 60) would be perfect and am planning to get it in around a year.
As far as tips for a new owner, from one to another:
- Don't force your bird to do anything at the outset. Grabbing it to pet it, or grabbing it to move it around will likely lead to a bitey bird. I know this from experience having owned budgies as a child. Conures I consider a fair bit more intelligent, or at least significantly more human-relateable, than budgies, which means they respond well if you learn to respect them as another intelligent being sharing your home.
- Teaching to step up by command or by context (my bird, Auri, attempts to step up whenever an outstretched finger is near her, and this morning attempted to step up on fingers that were handing her a treat from outside the cage, going for the fingers before noticing the treat!) will be the fastest way to your bird's heart. There are many online resources that detail many ways of teaching the step-up to birds having a variety of personalities, so I recommend finding which one fits your situation best and using that as a starting point.
Hope all goes well with you and your new friend!