Any updated documentation that discusses Virtualmin account plans an dvarious Virtualmin terms?

Hi, folks:
Does anyone know if any documentation has been written or has been updated regarding account plans and various virtualmin terms?
I know virtual servers are actually consdiered domains.
But what about alias and non-alias servers, and various other terms like that other htan meail inboxes, mySQL databases, disk space, bandwidth, and such?
If these terms cna actually be clarified somewhat it would sure help a lot.
Also, I have a unique question here, and was wondering if anyone experienced in this type of thing might be able to provide an example of how I’d do this.
I’m setting up an audio-based hosting package.
It’s specificly designed for a specific type of customer, though, and I doubt many will go after it.
However, hear is the deal.
I’d still like a virtual server to be created for the customer, however rather than requiring a traditional domain that I know this customer won’t be able to pay for, I’d like it if he could use a sub-domain of an existing one in the server already upon account creation.
That sub-domain, will depend on the customer at least I hope.
Any thoughts?

Right now, I’m teling Virtualmin to use “Default Settings” as a template for that package, and such.
Any modification suggestions are apprecaited, along with clarification on the temrs that I’ve asked about.
Thanks for clarifying this stuff, much appreciated, as some of the documentaiton I’ve found on account plans doesn’t even talk about this stuff like alias and non-alias servers, and is unmaintained, and considered outdated from what i can find.
Other results specificly pointing at the words “Accoutn plans” go to Cloudmin something I’m not even using.
At least, for now.
Someday, though? We’ll see!