Premium accounts for personal

[Kenneth]

1) We already signed up Premium membership for few colleague. But only allow us to enjoy premium service within the workspace.

Is there anyway i can sign up premium for each person? Meaning they can enjoy premium service for their own workspace?

2) Since current premium account is based on workspace, is it mean will be charge again if I join another workspace with same ID? 

[Daydreamer Mike]

Trello is billed per workspace, not per user so as such you can't mix and match free and premium across different workspaces (unless you have the budget for Enterprise).

So those persons in your premium workspace will have access to premium features while within your workspace but your premium access can not grant them premium in their own workspace unfortunately.

If you have them as premium members in your workspace, you could allow them to have private boards within your workspace

It is worth asking also if they need premium.  If they are a single user in their personal workspace, Trello Standard may be enough and is only $60/yr