CMS is a complete platform that runs on a Unix system, costs are also depending on the authorisation of the system by Avaya. Pricing I don't have a clue.
BCMSVu on the other hand is an application that runs on a Windows NT4 SP6 or W2k PC for the server. You can run the client as well on the server or on a W95-, or W98-, W2k-platform.
As previous mentioned BCMSVu is pretty basic for more detailed reporting you have to take a step to the higher level as the CMS, but this higher level also expresses itself in the price.
In the switch as well it must be configured in the system customer-options before you can use any of the two systems.
So this also needs probably some authorisation.
So far I did installations for both the systems, but pricing has never come to my ear.
Hope this helps..
John