Used Pbx System

In addition, there are other pending messaging equipment on the market please list them (if possible) and provide a source link. With all the answers please provide a source link if possible. Thank you.

You will probably find that the software is a better solution. You can get a virtual PBX as Axon, which is less expensive than a hardware PBX more scalable, and you have more flexibility to customize a system with only the features you want. And you can use software or phone lines with VoIP is cheaper, or with standard analog telephone lines with the use of a telephony board to connect to the computer. Here are some links for you to take a look at:

Axon Virtual PBX:
http://www.nch.com.au/pbx/index.html

IMS On Hold Player Message:
http://www.nch.com.au/ims/index.html

Phone cards:
http://www.altoedge.com/telephony/index. ...