Note the carriage call for #123 at the 35th Street entrance. And in this photo, #232.

A good history of this retailer and building can be found here. The bronze canopy on the 35th Street side was removed in 1914 after it caused a woman's death. Below is a street view of the B. Altman & Co. emporium building today. The retail powerhouse held its final sale in November 1989. Today the building is a mixed-use structure. Swing to the right in Street View to see the building Notcom referenced, under construction across the street in 1906. In the two photos of B. Altman posted, the construction site is pretty much the same, leading one to think the photos were taken on the same day and near the same time. But, the window displays have been changed. So, probably not taken on the same day. They sure used a lot of fabric.

returns may be more involved than you think: that construction - demolition? - site in the foreground is occupied by a 1908ish building that goes by the name of New York Accessories Exchange (and people today think shopping is an ordeal!) Just be sure to keep your receipt.

The poster at lower right offers Blanche Ring singing on Monday October 8, which was indeed a date in 1906. Ring was known for In The Good Old Summertime, and slightly bawdy The Belle of Avenoo A, which you can hear in this 1970s revue version https://youtu.be/BeIVf9k2zgg?si=MssupKhNEMFS_3EI