On DreamHost mail is stored in the Maildir directory within your Home directory. Accessing the data should not be a problem.
Only if you decide to set one. You can set the storage limit on any mailbox you create, up to the limits of your particular hosting account.
Yes. The attachment limit is 40MB for both incoming and outgoing mail.
Yes, but apparently you may encounter problems with IMAP/SSL when accessing mail.yourdomain.com, due to the DreamHost SSL certificate being for mail.dreamhost.com. More information can be found at the link below;
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