hey guys,
I found that SDKBOX supports IAP with blueprint also.
Here’s the link to the documentation.
http://docs.sdkbox.com/en/unreal/iap/
I also use to get their support in considerable amount of time
It’s really nice and free and the fastest way I found to integrate into my game.
any queries drop an email to support@sdkbox.com and they replies within a day.