I currently have my new Syrian hamster in my Duna funa after my hamster that was in it passed on and I dicided against putting an untamed hamster in Rotastak. In order to give him more room, for a bigger wheel and space for another house/flying saucer i took out the shelf that was on the bottom and attatched a bird ladder to the top shelf so he could get onto it. There is a good ammount of hight and space now so i was able to place a syrian sized wheel into it. Im able to fit in his foodbowl/sand bath/a freestanding syrian sized wheel/flying saucer/snack shack/hamster igloo and lots of tubes for him to play in. I will post some photos of my mods when i take some