For every type of use case, there is a phone model to fit it. Costs will vary depending on whether you select a high-end phone brand or a generic option. Your options could include: Screen Type: Color screens, grayscale screens, and screen-less phones are three common options. Sizes of screens can also range significantly. Buttons: The number of function buttons on business phones can range from 2-12. Wireless Options: Certain jobs or environments may require wireless phones that can be physically transported throughout the office or work site. Audio Definition: You may choose to upgrade standard audio to HD audio. Phone Size: The size of business phones can vary significantly, from large phones designed for conference rooms, to “standard” sized desk phones, to small, lightweight wireless models.
A virtual phone number is a telephone number without a phone line directly associated with it. Instead of being connected to one specific telephone line, a virtual number is programmed to forward incoming calls to one of the pre-set telephone lines that the client chooses, be it fixed, mobile or VoIP. Virtual phone numbers are also known as access numbers since they can work as a gateway between traditional calls and VoIP.

I’m actively researching phone services for our company, and I agree with some of the others. This is an overview more than a review, doesn’t go in-depth enuff. But, it’s a good start for me, I did find it helpful, weblinks are easily accessible. Just not as informative as I’d expected and hoped.
The AT&T Synapse works the way you do — no headaches, hassles or hidden costs. Large backlit displays, web-based system administration, familiar call handling and features, scheduled-based auto attendant, built-in voicemail, dial-by-name (first or last) functionality, and inbound call routing rules, the Synapse has the most features in its class.