For its members only, Costco offers the Rubbermaid Brilliance 18-Piece Food Storage Set for $17.99 with free shipping. That's $2 under our May mention and the lowest price we could find by $13. The containers range from .5 cups to 9.6 cups in size.
Before you spend another dollar on items and services like these, check with your public library. You will likely be surprised by what it offers for free.