An important dimension of client-consultant negotiation is the outcome of the case under discussion. Normally consultants promote their services by making tall claims but reduce their overall responsibility to sort of zero obligation and craft all escape routes in the agreement by skillfully putting entire burden away from them. Quite naturally a client is more interested in the final outcome in a timely manner than the qualifications or impressive success stories posted on the websites of consultants. Particularly while talking to the legal attorneys one needs to remind them of the following quotation of the former president of USA , late Mr. John F. Kennedy:: 

" You cannot negotiate with people who say what is mine is mine and what is yours is negotiable"

Attorneys and consultants talk too much about the value of their time but forget the value of client's money which is equally valuable for the client. They resist to agree that the failure to get final outcome may be a consequence of their incorrect presentation or filing or incorrect application of related laws and procedures. They try to hide behind the excuse of the law which prohibits them to guarantee the outcome but probably forget that the professional ethics would never allow faulty or flawed preparation through their assistants and clerks. 
Reading their agreement, it appears as if they are hiring the client and by signing the retainer agreement and paying the fee client will become responsible for doing everything the attorney/consultant orders her/him to do. But in the same agreement they quietly include a clause that the outcome is not guaranteed (even when the client fulfills all the terms of his/her responsibility) . In the given situation, a sensible and skeptical client is left with no option but to thoroughly satisfy him/herself before engaging the consultant and if consultant is not willing to talk to him without fee, then I think both are equally smart.