I need a small all-metal cage to put my rats in while I clean their regular cage, because they've chewed through or gotten out of everything else they've been put in. I would like to find a cheap one because I don't have a lot to spend. I just want one level, and it doesn't have to be very big. The closest thing I have found is the Ware Chew Proof Small Critter Cage, and that would be ideal but it is $40 at the cheapest. Any ideas?