Can you define what you mean by broker? Somehow I don't think that word means what you think it does.
A broker? If you're on your own, you might want to consider working with several, everyone you can find. I also assume that if you're talking about working with brokers that you intend to get your authority. I'm not sure I can give any advice without knowing how it is that you're thinking of operating, whether leased on to a carrier or with your authority.