How do I hide Accounts from specific levels, but allow then to be available for other levels on the same sheet?
If you are working on a Standard sheet, do the following:
Navigate to Modeling > Sheets > "Edit" your Sheet > "Edit" Customization for Sub-Levels. You will see the Accounts on the left and levels on the right. Expand the accounts on the left and then select the account that you would like to customize the level availability. Next, expand the levels on the right. You will have three options for an account: Hidden, Read Only, or Editable. You can restrict at parent levels to expedite the process (as the setting will be inherited by the child levels).
If you are working on a Cube sheet, you can create restrictions that limit the availability of accounts for each level. To do this, navigate to Modeling > Sheets > "Edit" your Cube Sheet > "Edit" Restrictions. You can create a Level-Account restriction and then customize that way.