Required Linux System Administration freelancer for Mail server set-up job

We are using a go-daddy server and as you know it has smtp relays limitations. Hence, we are planning to implement our own smtp server. Can you do that? If yes, below are the details of what is expected from you.

Explain to me how you would do it, in your proposal.
The set-up should be concrete and emails should not bounce
We should be able to easily switch between our and go-daddy's smtp server
emails should be ssl secured, we have the certificate
all existing emails should be migrated to new smtp server
Suggest what will be the downtime needed
Would you be able to document everything?

Skills & Expertise Required

Linux System Administration