Rupankar,
There are a number of talented consultants who operate in the contact center space, you can find a number listed on www.callcenterguide.com.
As always, make sure the consultant has experience doing what you require, check references and sign a written agreement with an arbitration or mediation clause (eliminates potential problems downstream). Be prepared to provide the consultant with all the information they require; your immediate need ( 20 seat facility, VoIP, tech support etc.) as well as your longer term plans ( will the center grow, will there be other centers if so when, where etc.), how you will measure and determine success of the project etc.
A good consultant will have experience with; VoIP, many of the vendors and other contact center technologies in addition to possessing a wealth of knowledge about contact center operations, processes, methodologies etc. (often it is these latter points that determine the effectiveness and efficiency of any contact center).
Paying very close attention to Dave's warning...this is not an advert, but in fact I am a consultant.
If I can be of further assistance please feel free to contact me directly at ctaylor@thetaylorreachgroup.com
Colin |