I just built a rack and its not very expensive at all. If you can't afford it now perhaps in the future you will look into it. The wood involved is cheap to save money you could buy 2x4's and cut them in half to make your own 2x2's.
I also put together a watering system for about $40. In the beginning water bottles will work fine.
If you do build a rack you want tubs that not too deep because the idea is you put the food on top and they eat it through the hardware cloth.. Or you could do like me and get a deep tub but build a platform inside they can climb up to get the food/water.
apparently you can find some cement mixing tubs at lowes that are prefect and cheap. I am in canada and the lowes here doesn't have them
If your only building 4 enclosures the rack will be small and easier to move than a dresser.