In my opinion you should engage your own representation sooner than later. Often clients call me after they have had an interaction with a listing broker and this can lead to problems in bringing us on board. The #1 reason a client calls after already beginning a discussion/negotiation on a property? They quickly realize there is no financial benefit gained and the listing agent does not represent their interests. They feel at a great disadvantage or perhaps even dissatisfied with the level of service they are receiving from the listing agent. So whether you are going to engage us or any of the other highly qualified agents out there; do it now!
Find an agent you are comfortable working with, set the ground rules to play by (you are the boss!) Regardless of how you feel about "brokers/the system" you will be better served with your own representation.