Where a single computer with Tally.ERP 9 is adequate for your operations, the Silver edition is what you need. A 'user' in this context is actually a computer system.
This edition comes with all the features & capabilities including Tally Software Services like Remote Access.
With Silver you can manage as many companies (business entities) and personal books of accounts as you need.
You can also create as many users as you need, and provide each with the appropriate level of security. Your only restriction is that these users will all need to access Tally.ERP 9 from the system on which it is activated (licensed).
Since Silver supports Remote Access as well, you can authorise access to your Chartered Accountant, who with his Auditors' Edition of Tally.ERP 9, can remotely provide audit, compliance and advisory services.
Similarly your Tally Service Partner can, via Remote Access, answer your queries and provide support.
As a Silver user, you can create one TSS identity, which you can use to login to your own system from home or while on the move. Other users of Tally.ERP 9 can also grant access to you by authorizing this TSS identity.