Sorry, Judy, this forum never showed up as unread for me this week, so I hadn't seen this. If you make your display with fake plants that are easily removable, it will be easy to clean the gecko poop off where you're most likely to find it (my big guys always go on the plants, and the little guys usually do).

Alternatively, if you use real plants and peat moss for your substrate, all you have to do is mix the poop into the substrate and add water occasionally and it will break down just like it would outdoors, or pull out the plants and rinse the leaves at the sink every week or two. My big gecko cage does not stink at all, ever, and the little one smells of moisture, dirt, and live plants, a pleasant enough natural odor. The geckos do poop regularly, but their poop is dime-sized or smaller and similar to bird poo in consistency.

If you keep any critter, it's going to poo. On the scale of poo odor for household pets, with mouse poo being a 9, cat poo generally being around a 6, and ball python poo being about a 4, crestie poo is going to be about a 1 or maybe 2.

Cresties are nocturnal, so you won't see them playing much in the daytime, but if you arrange your cage well you will still see them. Other animals that come to mind as being suitable for the 45-tall are pretty much any gecko you can think of, including other rhacs (not leachies -- too big for it), tokay, house, golden, leaf-tail, etc., though obviously the height would be wasted on terrestrial species such as leos or fat tails. Also fish, anoles, arboreal or semi-arboreal snakes, rats, or a ferret ought to be happy in that.