We have a single Business Unit (BU) for our organisation. We are working with some external agency who design email templates for us. We want to give them access only to 4 Data Extension and not other DE as we don't want to expose our data.
I planning to create a new BU for this purpose and then share only these 4 DE with the child BU.
My question is,
Is this okay/good practice to create a separate BU for this use case? Does this affect any of the data in the Parent BU?
Also will the user be able to access all our current content within Email Studio in the new Child BU?