It would be great if in the context view, the context variables would be indicating with a green or red icon if they are being used or not. Very often it happens that I lose the need of a variable in a context group, but it's hard to remember if it is needed any more.
The price depends on edition, license type, number of users or environments and concurrent users and whatever you negotiate. I suggest contact firstname.lastname@example.org. I am sure they will be happy to hear from you