heres a suggestion that worked for me when one of my leos got out. I know it seems kinda obvious and probably stupid, but it wasnt to me at first, lol. Dont tear everything apart looking for her. like if you are looking for her in a closet, at first, dont move stuff around. instead, leave all the lights out, and just use a flashlight to look under things, without moving them. same with anything else, just dont move them right away if you can just shine a flashlight underneath, keeping the light out. That way she wont get scared and crawl off again and you miss her, to somewhere that you may already have looked, nearby. she will be more prone to just stay put.
I tore my whole apartment apart looking for my leo, for two days straight. I pulled everything out of the closets a bunch of times and was convinced that she crawled out of the apartment under the door (its a teeny one bedroom, not many places to go at all.) Couldnt find her at all. Then one night, right before bed i decided to try one last look. all i did was open a closet and shine the flashlight around where i could get it and left all the lights out. sure enough, I saw a tail! So now she is safe and sound. Good luck finding your leo 
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~Melissa~
1.3 Leopard geckos (Guido, Oasis, Gypsy, Marli)
1.0 Bearded dragon (Pharoah)
1.0 Hog Island Boa (Michelangelo)
0.0.1 Crested Gecko (Picasso)
1.0 Ferret (da Vinci)
0.1 Chinchilla (Eevie)
And Jack the cat!
Melissas Menagerie