Can you build the critter nation without the shelf and wheels and put it on a table/desk or is that not possible? Also, if it is possible and I end up getting it, should I get a double or single for two male rats? TIA!
It is really heavy though. A single would be difficult to find a sturdy desk for and I don't think you could do it with a double. And you just need a single for your two little males anyways.