You can try a storage cube cage. I have a hedgie tower, with three cages, and I have a second separate cage on top. It's plenty strong, and I often will store my extra wheels on top if I buy new bags of food and my other storage space is full.
I've reinforced the cage with billions of zip ties, which despite being tedious, was very easy to do.
I've reinforced the cage with billions of zip ties, which despite being tedious, was very easy to do.