I currently have a cage big enough for two rats, which the two I currently have (one isn't mine, just staying with me till his owner can get everything set up. He was a bit of a rushed decision on their part.) do okay in, plenty of space for them. I want to be able to get more rats in the future though, like, be an option for people who get rats at the local pet stores and then realize they can't handle them, etc. So I'm thinking I'd probably need to get a few single rat cages for rats that don't do too well with others/two week waiting for health period/etc and maybe three or four of the larger ones that could hold multiple rats? (My plan is to do this over a couple of years as I see the need...there aren't any rescues around here.) So yeah. Cages that aren't too expensive but could be reasonable for a group of rats (if it's expensive but has decent sales every now and again that works too.) Please and thanks guys.