Although counterintuitive, I find that on a cold call, expressing uncertainty to your prospect about whether or not your service is a fit for them helps lower their resistance level and relate to you more as a person. Examples would be ‘I’m not sure whether it’s a fit for you at this point, it may be, it may not be, but thought it was worth at least determining that together.’  OR ‘If this ends up not being a fit for you, that’s not a problem, but figured it was worth talking.’