Bulk Email Verification & Cleaning Vendor Needed

We are looking for an experienced person/vendor to clean and verify a large email database with a strong focus on high accuracy and very competitive pricing. We need checks such as: Syntax & formatting Domain/DNS/MX validation Mailbox/SMTP verification where possible Invalid/undeliverable emails Catch-all detection Disposable/temporary emails Role-based emails Risk/unknown classification We are especially interested in vendors who have their own tools, scripts, APIs, infrastructure, or alternative verification methods that can deliver reliable results at a significantly lower cost than standard email verification platforms. Requirements High verification accuracy Ability to process large volumes Clear Valid / Invalid / Risky / Unknown classification CSV/Excel output Competitive bulk pricing Data privacy/security Sample/test batch before full processing Please Include Your verification methodology/tools Expected accuracy/reliability Pricing per / 1M emails Processing capacity & turnaround time How you handle catch-all, disposable and risky emails Whether you can provide a test batch? Relevant experience with bulk email verification Long-term collaboration is possible for the right vendor based on accuracy, pricing and turnaround time.