Hello. This spring/summer we are going to clean out are basement (it is like 700-1000 square feet). It is L shaped, in one part is the water heater and the washer/dryer, in the other part my brother is going to have his "golf shop" to make his clubs, then on one part of the wall there are going to be bookcases (filled with ALL my books, need suggestions for good herp books), then finally there is going to be room for my HERPS. I would rather house all my herps in comfortable nice looking cages than in racks. The thing is, that i hear lots about cages sagging when stacked, i dont want that to happen. What materials could i use to make cost effective cages that dont sag when stacked? Here is what is going to be kept in the cages.

-Some (3-5) female leos
-some (3-5) crested geckos (females in one cage, males indidvidually)
-A uro or two
-some BP's
-maybe a beardie or two
-some hogg island or caulker cay boas
-maybe a locality specific BCC or BCI
-hopefully a blue tegu
-maybe some bloods
-hopefully a ETB

As of now i only have a leo and a crested. By the end of this summer i hope to have a leo, crested, bp, and maybe a uro cage finished It will be gradual. But i hope to get more and more herps. So any ideas for making cages that wont sag is appreciated.
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0.1 "Tremper" looking Albino Leopard gecko (Lex)
0.0.1 tiger crested gecko (peachs)
1.1 Feral cats that we adopted (Fuzzy, and Bear)