...If we're building a secondary base specifically for hiding, we're going to want it someplace outside the residential area. Underground is probably out, but possibly we can find a secluded area in the park to put it. ...I know how to make a small scale teleporter, though I'd need to practice since I've only been shown how to make it, instead of actually doing it myself. But if I can get it running, we could have a quick escape between the regular treehouse and the more hidden base as well.

Does that work?