If you are going to be using leftovers effectively, it’s very important that you know how to store food correctly. The difference between storing food poorly and well can be the difference between three days or six days of usage. That’s money in your pocket!
As far as containers go, I recommend splurging for a nice set of glass storage containers. They keep the food airtight and are also easier to clean and don’t stain. You can freeze them without issue and microwave them safely. They are more expensive but worth every penny. I’ve had the same set for three or four years now, and they still look like new and work great.