Here is a brief description and key features of the required application.
1. It is supposed to pick listings from one website and list into other site/s automatically.
2. New listing process should be automatic but in controlled manner.
3. Certain features like price, shipping time should be adjustable.
4. Any changes to the origin listing should take effect automatically in the new listings.
5. It should be able to pick certain features like dimensions, description etc.
It is just a brief description but hopefully you'll have a rough idea what I am after.