What does a standalone Exchange plan give you?

It provides business mail hosting and Outlook on the web. Microsoft lists a 50 GB primary mailbox on Plan 1 and 100 GB on Plan 2. Compare separately if you also need desktop Office apps.

Who can answer from a shared address?

Give each person their own licensed Exchange Online mailbox and grant the appropriate rights to the shared inbox. Microsoft says a shared mailbox can store up to 50 GB without its own license. Higher storage and some archive or compliance features can require licensing.

Choose whether replies should come from the shared address or show that a person is replying on its behalf.

What must be ready before incoming mail moves?

Add and verify the custom domain, then create the mailboxes before changing the record that directs incoming mail. Leave any existing customer routing alone while you plan a test on a separate domain.

Exchange enforces sending limits. Keep the plan for sending and tracking app receipts separate from the team inbox.

What does an Outlook export leave behind?

Microsoft documents exporting mailbox items to a PST file from supported Outlook desktop versions. Check your version and which items are available locally. Classic Outlook’s export does not include items such as message rules or folder permissions.

Test what the destination can open before closing the old mailbox. Keep a separate record of team access and shared-address settings.

How would you plan a support inbox for two people?

Draw a fictional team with no account or settings changes.

List the addresses
Write a personal address for each teammate and one shared address for questions.
Trace a message
Mark who can open the shared inbox and who can send from its address.
Leave a rollback point
Before changing routing, check that the destination addresses exist and write down how you would restore the previous route.