Configure SPF, DKIM, DMARC

My domain’s messages are clipping spam filters more often than I’d like, so it’s time to tighten the authentication layer and boost overall deliverability. I already host mail through a third-party service (neither Google Workspace nor Microsoft 365), but the DNS for the domain is under my control... (Budget: ₹1500 - ₹12500 INR, Jobs: Active Directory, DNS, Email Marketing, Linux, System Admin, Technical Documentation, Troubleshooting, Web Hosting)