When selling finance-related products like life insurance which is the best way to get to the market?

Is it more effective to get them individually or by targeting a group for instance by making a presentation to all the employees of the company? I have been in the market for 2 months now but going from one person to another has been quite challenging. I am of the view that perhaps the most effective way is through the theory of large numbers whereby one conducts a presentation to a number of prospects then goes on to later attend to individual needs. Kindly advice on the two approaches.