ONE fashion mock-up is considered one top and one bottom. One color is considered one mock-up as well. Essentially one whole outfit.
One front view of the outfit is considered ONE mock-up. One back view of the outfit is considered ONE mock-up.
In the event that you do not have a full outfit that you need for a mock-up, one shirt by itself for ex. is ONE mock-up. One accessory, is considered ONE mock-up.