Call Accounting/CDR are available with the UC500, based on existing CME feature. CME GUI has a call history report, not very feature rich but will tell you calls though the system.
Today customer has a number of choice choices;
1) Use a External FTP server or store on flash memory* (Easy and Reliable implementation) You can configure the UC500 / CME to store CDR's on the UC500 in a CSV file. This CSV file can the be uploaded of the box using FTP and manipulated as required
* writing data to flash is not recommended since UC520 flash is only 128M and is near full at this point
3)Use a External Radius Server (Advanced Implementation) You can deploy a separate Radius server/PC to collect the CDR Records. These records could then be exported to Excel or some database application and create/run reports for their use: Setup & Configuration Guide Sample Configuration Sample CDRs
4) Use a 3rd party billing tool that integrates with Cisco e.g.