SECONDS - these plants need some TLC hence the price. They have 1-2 leaves and marks/browning to the leaves. You are buying these for the plants they will become! 

These beautiful plants set themselves apart from the generic green plants - sure the top of the leaves are green - they need some chlorophyll (which appears green) to photosynthesise to make energy -  on their dark green leaves they have light green stripes with beautiful pink stripes running through them. The underside of this stunning leaf is a wonderful deep purple. Held up to the light you can see through the bottom of the leaf to see its stunning structure. 
They enjoy medium - bright indirect sunlight. Water when the top of the soil is dry and do not leave standing in water. They won't say no to a misting once or twice a week if in low humidity. 
These are mini plants that make a great way to add one to your collection cheaply and for you to enjoy its development. 
They come in a 6cm pot and stand 15-20cm tall (from base of pot)

Calathea Beauty Star seconds - Variegated Green/Light Green/Pink Leaves