In-App Purchases: Money back guarantee?

Hey. I would like to offer non-consumable in-app purchases in my IOS app and was wondering if I have to offer a money-back guarantee for non-consumable in-app purchases? So if someone buys my app, can they return it? Or is that generally not possible with non-consumable in-app purchases? If there is no money-back guarantee, do I have to point this out to the users? In addition, I was wondering if there are bugs in my app that I didn't know about, do I have to give all my buyers their money back? Because I then sold a defective product... I would be happy to get a answer.

In-App Purchases: Money back guarantee?
 
 
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