I lost mine for a while yesterday(fell asleep with her out, not one of my best moves). I spent all morning looking for her before going to work and wound up coming home on my lunch break to try and find her.

After tearing apart the entire apartment(including refridgerator and oven) I found that she had climbed up on top of a tub(about 3 feet tall) and climbd up on top of two smaller containers before going inside a box on top that was open. In total, she was about 4 feet off above the floor.

My point in this story is don't underestimate their ability to climb. They can get a lot higher than you would initially imagine.