Ask HN: How much can startup charge Amazon for providing a service?

Hi there! What do you think may be the best model for a startup to charge Amazon for a data/service which will be supplied for Amazon mobile app/site? Flat monthly fee? Per API call after user's request coming from Amazon? Given that deal doesn't have to be exclusive so there will be options to supply the same data to other companies?

And ideally we want to avoid the acquisition offer.

Oh the headache...