3 Websites Migration, Google Tracking Setup & Full A–Z Testing

I am looking for an experienced developer to help migrate 3 existing websites/domains from our old projects to new projects and make sure everything continues working perfectly before and after the migration... (Budget: $30 - $250 USD, Jobs: API Integration, DNS, Google Analytics, Google Search, Google Tag Management, HTML, Troubleshooting, Vercel, Website Optimization, Website Testing)