i unfortunately have worked, and am about to start work in telesales. I used to represent an energy company called EDP. Which was guaranteed, 100% to reduce your energy bills. If someone proved they were on £300 a quarter energy bills, we would do like £220. Simple as that, we did it cheaper.
However, convincing the customers of that, was a different story. I got called pretty much every name there is, I got threatened with death countless times, as did my family.
All because I called to see if they wanted cheaper gas/electric/water rates.