Critical System Protection Log Storage

We are in the process of trying to estimate the size of the file share storage that we will be storing our bulk logs onto.  We are unsure about what size of storage or disk space is needed to store our bulk logs.  We are planning to deploy agents to 10,500 devices.  The logs will be rolled up every 24 hours and brought back to the server.  We are planning to keep a 3 months of current logs on the server and 10 months onto tape for PCI compliance and investigative purposes.  We need help in trying to find out the size of the storage.  Any help would be appreciated.