To celebrate girls growth and good health, dolls dressed in Heian period costumes are displayed on a tiered stand. These dolls represent the Emperor and Empress, their noble court ladies in waiting and ministers.
The custom of displaying dolls began during the Heian period.
There is a certain order of the tiers of dolls. According to Wikipedia, the top tier hold the Emperor and Emperess dolls, usually in front of a gold folding screen and placed beside green Japanese trees. The traditional arrangement had the male on the right, while modern arrangements had him on the left (from the viewer's perspective).
The second tier holds three court ladies, each holding sake equipment.
The third tier holds five male musicians, each holding a musical instrument except the singer, who holds a fan.
Two ministers may be displayed on the fourth tier: the Minister of the Right ,and the Minister of the Left,. The Minister of the Right is depicted as a young person, while the Minister of the Left is much older. Also, because the dolls are placed in positions relative to each other, the Minister of the Right will be on the viewer's left and the Minister of the Left will be on the viewer's right. Both are sometimes equipped with bows and arrows.
The fifth tier holds three helpers or samurai as the protectors of the Emperor and Empress. Additional platforms can hold miniature furniture, tools, etc.
Families generally start to display the dolls in February and take them down immediately after the festival. Superstition says that leaving the dolls past March 4 will result in a late marriage for the daughter.
Here are some photos of displays I saw at the department store in the mall. I wonder if you can start small and add to it, spreading the cost over several years? Another question I have is whether girls are allowed to play with the dolls?