This sounds like something that could be achieved with some custom integration between the two API's, something that we specialise in at Dijitul. If you need help with this outside of the KashFlow environment but using their API's feel free to get in touch.
We are a listed KashFlow developer Dijitul more information can be seen here http://www.kashflow.com/developers/find-a-developer/ and here http://dijitul.uk/services/kashflow-integration/
@KashFlow Product Manager,
Had a look and can't see an option to integrate with Amazon, can you help us locate it?
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