Let say I get a new client who is an agent for "Big Global Corp." in Vancouver
I create them an account. Get the DNS all set up, and the Vancouver agent handles their emailing from newsletters.bigglobalcorp.com
Now let's say I get a client who is an agent for "Big Global Corp." in Toronto
I create them an account. Get the DNS all set up, and the Toronto agent handles their emailing from news.bigglobalcorp.com
Now let's say "Big Global Corp." headquarters in London decides "Hey, we like what Toronto and Vancouver are doing for mail. Let's create a company wide account." (marketing.bigglobalcorp.com) but each agent needs their own access.
Is there a way to setup something like
Each with their own login for their own account but billed to marketing.bigglobalcorp.com's account?
You can certainly have one account with multiple clients inside it, each with their own login, and have the main account owner pay for the campaigns.
They would all login at the same URL though.