The truth is, the concept of tapping into expired domain resources is fairly straightforward. You buy an expired domain name and put it back into action with a basic (or not so basic) website.
From that point on, you get to enjoy all the benefit of it’s related backlinks, traffic, and potential cash flow.
That’s ASSUMING you choose the “right” expired domain. Which means you chose one that does in fact have solid backlinks, traffic, and potential cash flow.