Most VoIP solutions will require stable and consistent internet connectivity at all your office locations where VoIP will be used. At the very least, your business phone system must have access to a business-class internet link, so discuss these needs with your company's internet service provider (ISP). This should be a dedicated link through a dedicated router if you expect your phone calls to sound as if they were coming from a business and not someone's home Skype connection. At a minimum, it's important to have a router that can create virtual LANs (VLANs) and also has the ability to encrypt your voice traffic. These days, you need end-to-end VoIP security for any call.
All that makes configuring and managing home routers very difficult for IT personnel, but they'll still be faced with that task because if employees run into conversation problems over their softphones, their first call will be to the IT help desk. Shunting them off to the VoIP provider, or worse, the ISP isn't a good idea either. It'll likely cause employee frustration since those outfits won't be familiar with your company and they'll either refuse support or it'll take a very long time.

The above eight rules of engagement for voicemail greetings may sound easy enough, but they’ll require some practice to get just right. Let’s look at some examples to provide some context in how to apply the rules to various types of greetings and situations.
But with integration being at the heart of VoIP and UCaaS, you can't make a purchasing decision here without thinking about the future. On one side, consider each vendor carefully to see what they've done over the last half-decade in terms of product development and keeping up with VoIP and UCaaS trends. On the other side, think about what you'll need in the next five years.