The apartment is designed to suggest the life of a successful photographer. Modernist architecture, designer furniture, photography equipment, books, and a carefully curated interior are meant to suggest a cultured and successful individual.
In contrast, smaller details — an ashtray with lipstick marks, a knocked-over bar stool, a handbag left behind, a single high heel near the final door — are meant to imply that something is wrong, and that something may have happened here.
Here, the photographs mainly function as progression, unlocking new areas of the apartment. In a larger production, they could instead reveal more narrative information and play a larger role in the storytelling.