For one time advertising promotions or typical requests it is easier to use services of the outsourced call center. Main advantage of such a service is that the company who rents it is free from the necessity of keeping the operators and organizing their work flow.
Lingo is one of the most affordable U.S. Internet phone services. Lingo offers unlimited local and long distance calls anywhere in the U.S., to Canada, and to Western Europe, plus over 25 calling features