Not taking into account the cost of building all the snake and rodent racks, converting a shed into a rodent building, or all the business expenses (like Tim mentioned) We spend about:

-175$/month in rodent food and bedding.
-30$/month in snake tub supplies (unprinted newspaper and deli cups).
-15$/month in cleaning supplies.
-Electricity....I also don't want to know

This is for about 100 snakes right now.

-Evan