1981 Buick Regal was the pace car for the Indy 500 that year, 100 replicas were sold through dealerships

https://en.wikipedia.org/wiki/Indianapolis_500_pace_cars#/media/File:1981_Indy_Pace_Car.jpg

The family that owned Bennett Buick in Wayland NY bought one and keep it in their collection
http://carzhunt.blogspot.com/2014/08/bennett-buick-1921.html they opened their dealership in 1921, and are still family owned.

Garber Buick in Saginaw is the oldest Buick dealership, they started in 1907
http://www.wnem.com/story/18874410/americas-oldest-buick-dealership-gets-a-facelift

Covert Buick in Austin Texas is still family owned, and Roberts Buick in Owenboro Kentucky... both started in 1912
http://forums.aaca.org/topic/5714-oldest-buick-dealership-still-operating/

http://buickcity.blogspot.com/2008/04/buick-research-gallery.html