And segmenting the users: no API access needed no extra cost, low API calls needed (still free tier but with limited quota - useful for you to know and to talk

And segmenting the users: no API access needed no extra cost, low API calls needed (still free tier but with limited quota - useful for you to know and to talk to them) and the big users with said block of prepaid calls (pass them through the free API tier first with a grace period).