As the title says, I'm thinking about getting a pair or so of crested geckos. Not for breeding or anything, just for personal pets. So I need/want to know a few general things.

I will house in glass tanks/aquariums/vivariums:
What will I need for heat as in temps, and sources?
Humidity?
What to feed and how often to feed?
Best substrate (depending on the size?) ?
Best size glass tank/etc for 2 (If even recommended to house together) ?
And how big do they get? In this one video I just saw on youtube, I saw 2 things that kind of looked like BIG cresties, at least an adults hand and a half big...

Anything else you guys can think of? Or, if you can send me a complete care sheet that would be awesome!