One main difference I noticed between a privately commissioned Book of Hours and one produced more generally was the difference in detail and subject of the detail. The Grandes Heures of Anne of Brittany is heavily illuminated with idealized images. However, we can tell this prayer book is specific to Anne of Brittany because the borders contain images of plants that are identified by name. These details were included because Anne of Brittany was heavily invested in her garden. In contrast, schools such as the Ghent-Bruge School of Illumination also produced heavily ornated manuscripts for sale. These books contain the same level of detail but are more general with their designs. Common designs seem to be seashells and other more picturesque florals.
Furthermore, I was fascinated by the baby Jesus Christ dolls because they seem to be an early form of toy dolls. This was interesting to me because it seems to parallel the usage of prayer figures where there’s the belief that how you treat the figure is correlated to your own life.