Restricted Application Subscription

I am having trouble figuring out how to manage the subscription workflow for an application that is restricted to certain users. I currently have to verify if a user is an "approved" user through an http request, and only after that do I want to have them be charged for a subscription. Is that possible with the in-app subscriptions? I am assuming my workflow would be something like "Customer Download from app store -> Customer submit email or MLS id for verification -> On approval, customer is presented with an in-app purchase screen"? Thanks.
Restricted Application Subscription
 
 
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