Small Bedroom Solution: The Half Loft | But there is another way—a solution that combines the space-saving advantages of a loft bed with the ease of a bed that's not seven feet in the air. Enter the half loft for storage solutions and under-bed storage options.
DIY cage idea: large box turned vertically (for limited space) and add different levels/platforms. Use some sort of varnish/sealant to protect wood from urine (make sure whatever is used is not going to be harmful to the rats!
16137 Blocky Premium Production Quality Black Velvet Female Chinchilla
Chinchilla or related item offered for sale or export on Chinchillas.com - 17210 Violet CCCU Royal Persian Angora Male with Ear Tufts Chinchilla