Essentially leveraging a space in your primary home as a rental that produces enough income to cover your living expenses. Duplexes are most commonly used in House Hacking techniques, but I’m not sure where historic century old homes fall in terms of commonality, although rest assured we’ll use that heavily when it comes time to market it as a rental.
“If we are always arriving and departing, it is also true that we are eternally anchored. One's destination is never a place but rather a new way of looking at things”. —Henry Miller