Live (driven) tooling adds powered mill/drill tools to a lathe's turret, letting a turning center do milling without moving the part to a second machine. It cuts cycle time and setups. On the used market, live tooling and Y-axis meaningfully raise a lathe's value.
See every Turning Centers & Lathes in the reference library, by make and model.
How this affects buying and selling: read The Gauge, or value any machine free at The Machine Blue Book.