A live-in flip is a renovation project you also happen to live in: buy a dated or distressed home as your primary residence, improve it over time — often with your own labor — and sell at the higher value. Compared with a conventional flip, you eliminate the second housing payment during the renovation and can move at a slower, cash-flow-friendly pace, at the cost of living in a construction zone.
The strategy's best-known appeal is tax treatment: current IRS rules allow many homeowners to exclude some or all of the gain on a primary residence they have owned and lived in long enough — the specifics and limits are exactly the kind of thing to confirm with your CPA before you count on them. The other math to respect is the renovation itself: like any flip, profit is made at purchase, and sweat equity only pays when the improvements are ones buyers actually value.
This is general educational information, not legal or tax advice. Rules vary by state and locality and change over time — check your local law and confirm specifics with a qualified professional.