Cold calling leads and potential leads

Basically we have leads that are people have bought that we are trying to get back on board. and we have leads who contacted us and never bought, and last we have leads that neither contacted us nor bought and we are trying to re build our pipline with buying customers. We dont need you to sell the deal but we do need you to make contact and make sure we are getting qualified people to call back and offer them our services. So you do need to be a good on the phone cause if they say no you need to convince them why they should use us and our product. We have a total as of right now of about 1000 leads, but if job is done well we will continue to have you do follow ups with new customers, potential customers etc... Thanks