You want business email with your business domain.com then yes you can buy workspace it seems you were routes to buy enterprise plan. You can buy cheaper one which is business plans or DM me for discount. More on reddit.com

Collaborative Inbox could do what you are trying to accomplish https://support.google.com/a/users/answer/167430?hl=en More on reddit.com

I have a server already but managing an email client, trying to keep it up to date, staying off blacklists, managing anti-virus, configuring mail delivery/transfer agents to fit my environment. Props to those who are fluent in those technologies, but I am not a back-end genie. I'm one of those guys. I've been doing it for ... well, a long time. And I'm thinking about offloading the mail to Fastmail. It's just becoming too much of a hassle even for those of us who have been doing it forever. Another reason is that with everyone using IMAP on mobile devices (and a lot of people not even owning computers), I can't have them download the mail using POP3 after a couple of weeks on the server; so the servers are forever running out of storage due to years or decades worth of mail. The only thing in IT that's more time-consuming and bothersome than managing a mail server is upgrading or migrating one. I've had a personal paid account with Fastmail for many years, and I really can't think of anything I dislike about them. I don't recall there ever being an outage. They also provide CalDAV and WebDAV services that work natively on iOS or Thunderbird, and can be made to work on Android with DAV5x. I have no complaints. Some people may be concerned that Fastmail is based in Australia. I'm not knowledgeable about Australian privacy laws; but then again, I'm not too impressed with our own the way they're being implemented these days. I figure that part is probably a wash. But anything is more private than Google. More on reddit.com

It's great that your business is growing! To use your custom domain for email services with Google, I think the Google Workspace Business Starter edition could be a good fit. You can learn more and sign up here: https://support.google.com/a/answer/53926?hl=en Once you get signed up, Google has a very helpful step by step guide to start using the services: https://support.google.com/a/answer/3035792?hl=en You will need to make some adjustments on the website DNS to prove ownership of the domain with a TXT record, as well as setting up Google's MX record values to recieve mail at the custom domain. These DNS changes won't impact your existing website (you will be adding more records, not deleting anything). More on reddit.com