Quote requests, supplier emails, invoices and customer replies should not depend on messy forwarding rules or half-finished domain records.
Yes. Bad mailbox routing or domain records can mean enquiries, replies and invoices are missed, delayed or treated as suspicious by mail systems.
They are DNS records that help mail systems decide whether email from your domain is legitimate and how to handle forged mail.
Yes. The provider matters less than making the DNS records, aliases, shared inboxes and access rules line up.
A short call is enough to work out whether this is a website, app, automation, IT or security job, and whether it is worth quoting.