Questions

Hi, I currently have an Android app published on the Google Play Store using Median on the standard plan. I would like to add Google Play billing so I can offer subscription purchases within my app. Could you please let me know, do I need to upgrade to the business plan to enable Google Play billing or is there a lower cost option or add-on available instead of upgrading to the full business plan? If an upgrade is required, what would the total monthly or annual cost be? And can I simply rebuild my existing app with the billing feature and submit it as an update to my current Google Play listing? I appreciate any guidance on the most cost-effective way to add this functionality. Thank you for your time, and I look forward to your reply.