Clarification on Microsoft Partner Program Registration Fee for Publisher Verification (Non-Profit Organization)

We are a non-profit organization currently integrating Microsoft Graph Calendar APIs into our application. As part of the OAuth consent and security requirements, we are required to complete Publisher Verification, which in turn requires enrolling in the Microsoft Partner Program (Partner Center).

During the Partner Center enrollment process, we are prompted to pay a registration fee of approximately ₹4,500 INR for a Company account.

Before proceeding, we would like official confirmation and clarity on the following points, as cost predictability is extremely important for us as a non-profit organization:

1. Is this ₹4,500 INR fee strictly a one-time registration fee, or are there any recurring (annual/monthly) charges associated with:
   • Partner Center account
   • Publisher Verification
   • Maintaining the verified publisher status
2. Are there any additional or hidden costs that may arise in the future related to:
   • Microsoft Graph Calendar API usage
   • OAuth consent screen usage
   • Partner Center account maintenance
   • Renewal or re-verification of publisher status
3. Are there any fee waivers, discounts, or alternative options available for non-profit organizations to complete Publisher Verification without incurring this cost?

Our application only requires Calendar integration and does not involve paid Microsoft services or marketplace publishing. We want to ensure there are no unexpected financial obligations before proceeding with enrollment.

We would appreciate an official confirmation or documentation reference clarifying these points so we can proceed confidently.