The Nethercutt Museum has a section that is a replication of an early car dealership (like the photos from Shorpy)

For the Shorpy photos of dealerships, check out an interior https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjlMutenTuoQtyRCXB7uGJ_C5lQQTzM58KM6McVvqRHzRj-k-onHaSFePrTjHSZcHT_wu17BG8YXDkwSBk0JoWwPzOK7PUZpkkfhcs9h0o3Zb8NoHD5Obp1Psu1CpnlJNg6n6KfBUZ682U/s1600-h/cars8.jpg or two in this post: http://justacarguy.blogspot.com/2008/11/automobiles-of-20s-and-before-from.html or an exterior: http://justacarguy.blogspot.com/2010/03/impressive-car-dealershp-architecture.html