Don't tell them what are you going to do. They will most probably hate the idea of becoming your customer, at least at start. So just don't do it for the sake

Don't tell them what are you going to do. They will most probably hate the idea of becoming your customer, at least at start. So just don't do it for the sake of good relationship with this employer. Also a lesson of being independent which you know already: you don't have to excuse yourself. Do your stuff and move on.