Vague questions like “how much does it cost” to setup a call center are simply pointless. How much does it cost to build a house? Now what would the answer be? You CANNOT tell by only this information. You need more facts. Same is the case with call centers. Where do you want to open it? What is the purpose of the call center? There are so many questions that need to be answered before one can actually go about running a call center.
As for technology, Five9 is the world leader in hosted VoIP services. For the quality, it is the most cost effective solution around. People who actually know what they are doing use services such as Five9. Others can find many local/Indian solutions. Oh by the way I have NEVER seen such a center run for too long. Bottom line, do NOT try to save money on technology or Human Resource.