Dockerised Dovecot Email Migration

I need a clean, Docker-based email server running on Ubuntu with Dovecot handling IMAP/POP and SMTP relayed through Postfix inside the same stack. The instance must include reliable webmail access—Roundcube or similar is fine as long as it sits in its own container and authenticates against Dovecot... (Budget: $250 - $251 USD, Jobs: Docker, Docker Compose, Dovecot, Email Handling, Linux, Postfix, System Admin)