Lower env (stage or sandbox) testing approach for connectors

[crazyrohila]

We are thinking to use the Airbyte as connectors solution with in-house ETL pipeline. One thing that came up during discussion is, how connector has to be tested on lower environment. it would be great if people can throw some light on how they are testing connectors (specially marketing connectors) - include authentication, authorisation and campaign data.

Use case here would be, our app won't be the user of connectors but providing service on top of what is pulled from connectors. Airbyte will be part of the application as a component which allows user to connect account and pull data. What we are stuck at is, we want to test the connector ourself as part of whole journey, before we allow that connector to be available to end user.

Our understanding (and limited approach) is, some of the platform provide sandbox account which has limitation. Only way to test whole flow is, having actual account with targeted platform (trial or purchased ones) and the create dummy campaign. Each platform has different way to connect (via apps or account credentials) and permissions set for diff people assigned in those accounts. Is there a different or easier way to approach this instead of creating accounts for each of them before rolling out to actual client production accounts?