DETROIT—Saying it had radically reenvisioned the very concept of the autonomous vehicle, Buick on Tuesday unveiled the first-ever self-buying car. “In what marks a watershed moment for this company, we here at Buick are proud to present the first and only car that purchases itself,” said Buick spokesman Matt Grossinger, calling the new Buick Acquisition revolutionary in its ability to put a down payment on itself automatically, removing the need for any human initiative at all. “Consumers can sit back and relax while the car evaluates different loan plans and warranties completely on its own, not to mention negotiate its own selling price with the dealer. In fact, buying a car will soon be as easy as looking outside your window to discover your existing car has been traded in, and a Buick has been parked in its place.” At press time, despite the new technology, Buick sales remained stagnant.