If you're a natural salesman, you will do well. However, apply with caution. They were using many portals, including a British gas portal, which tell them when current companies' energy contracts expire. They would explicitly say that you are not allowed to tell the customer you have access to this portal. Therefore, they are working very much in the grey area at the least, and I expect that actually they are probably working illegally within their means and should they be looked into closer, I would doubt they will be allowed to keep running as a company.