Question about Returns

So I'm starting a Dropshipping page on eBay and i have a question.

Example: If i sell a Smartwatch A in ebay which I've bought from Amazon and put the delivery address to the customers home. Does the customer get all the paperwork? What if the customer finds that the product is broken? Is it hard to communicate to the customer and try to refund it together to Amazon.

Is AliExpress as hard or?

Thanks in advance,

Kalle