Hopefully it comes with a free vacuum for the interior. Of all the iterations of these B-body wagons (man, it feels weird to refer to anything other than a Mopar as a "B-body"), I always thought Buick had the nicest dash.
Engine light has been on for the 3 yrs. that I've owned the car but it runs just fine. Well that's NOT the sign of a well maintained car!
While that's possible, it could be something as simple as a vacuum leak or something else very minor. The hoses on that car are sure to be getting past their lifespan.