If you want a good cage for less than 200$ then the Petco Rat Manor is a good choice for 2-3 females or 2 males, I got mine new for around 70$. If you want to you can take all the levels out including the large middle level. 
http://www.petco.com/product/106171...t=MM_SmallAnimalSupplies_CagesHabitatsHutches
http://www.petco.com/product/106171...t=MM_SmallAnimalSupplies_CagesHabitatsHutches