I'm not familiar with your experience level, but if you're just starting out, I recommend a simple Brute trash can or a Rubbermaid tub etc like
@rygh is suggesting. Mix a few hundred gallons of water, get used to the process, how much water you'll need for your tank, what salt you want to use, how you are using the available space, get used to your rodi system (deal with a couple floods), before spending hundreds of dollars on storage containers. If you wait you'll have experience and knowledge of how you can setup a system to most benefit you.
That said, what you have pictured is a relatively common setup I think.
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