Diy Reptile Cage

Idiots guide to DIY cages?
I have so many animals its getting a little expensive to buy caging for them…not that I begrudge them the money but I find most cages are pretty badly designed and built, and there’s a lot of features I could have done with that are missing. The thing is I’m a total DIY idiot, but I think I could put together a wire or wooden box for an animal. Can any DIY-ers point me in the right direction for sites for making small animal and Reptile Cages? Thanks!
This is a good cage that is fairly easy to make.
http://www.ratfanclub.org/cagepln.html
I used a mortar mixing pan, instead of the cement mixing pan, and the three foot tall hardware cloth, instead of the two foot tall hardware cloth; so I needed to adjust my measurements slightly.
Here are some more cage plans, but not all of the links work.
http://www.curiosityrats.com/infodiy.html
I keep my Gopher snake in a 55 gallon plexiglass tank.
DIY Reptile Enclosures and Reptile Room Part 1