The latest version of Cisco Unity that I would recommend to a customer is 7.0. The most current version you can buy is 8.0. 70 users is a really small deployment so what you buy would really depend on your requirements. Unity can be deployed as UM or voicemail only. For UM, you could buy a 7825 server with and licensing for your users and have plenty of capacity left assuming you have no redundancy requirement. If you are going to go voicemail only, I would recommend Unity Connection instead. Recommended version right now would be 7.1(3b)SU2; however, 8.0 is available. As an alternative, if you do not already have CUCM - then you could opt for the CUCM Business Edition which is more than adequate for your user base (size wise) and includes both CUCM and Unity Connection co-installed on a custom 7828 server platform.
Hailey
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