Hello,
Thank you for reaching out here in the DocuSign Community.
Yes, once a user is removed from the corporate account, their emails become freed up so that they can create their personal accounts or their free accounts: https://support.docusign.com/s/articles/What-are-my-options-for-a-DocuSign-Trial-account
Also, any recipient can sign documents without the need for an account, however, in regard to storage, if they would want a place to lookup documents that were sent to them via DocuSign, they would need at least a free account.
Let us know if you need further assistance with this.
Best regards,
Nathaly | DocuSign Community Moderator
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