Considering that I am an SQF and BRC Consultant - if I was the potential client (you) I'd be asking the BRC Consultant what their specific services are - some consultants simply do a retainer and then provide you with guidance as you and your staff put together the needed documentation and then assist on over the shoulder guidance during implementation, and possible presense during your audit.
Some consultants are relatively limited in scope while others are quite well versed in all facets/all areas, etc.
and this is why you should first determine with your CEO what you want from a Consultant - otherwise you'll ask what the consultant can do and they will end up telling you what they will do for you.
The idea is a give and take - as an example (and I'm not a potential consultant for your company)...
When someone calls me up and wants to get SQF or BRC certified I begin asking a lot of questions and that comes from my auditing days in SQF and BRC and others - but I need to determine the why, how, when, etc, what shape their current FSMS is in, info and condition info on the facility, the current food safety culture, the dedication level of ownership, how they see using us as their consultants, etc.
So, together in a nut-shell we (the client and us) determine what is best for the client and that may mean that they will get on our eConsultant program and we guide them thru their own development, we review video of the interior areas and determine capital and operational needs, we'll do a gap analysis, etc. or it could mean going on-site for upwards of 30 days to do everything in person.
We normally spend about 30 minutes on the phone (even though a recent potential client and I spent about an hour and a half) discussing needs and non-needs, costs of the project, do they want on-site or off-site, if they have their own jet, hotel, etc, and all the fine details of their operation.
I'd also be telling them to bring referrences if they have not already provided them - we send them with our service offer after speaking with people.
Your prospective consultant may (like we do) have stream-lined a couple of different options for you that include various components - that helps to save some money most times as we have found by offering commonly used approaches we can cut down on expenses for our clients.
Then there is the need to have a good relationship, meaning people don't always get along with other people, we would like to think that everybody will get along with us - and us with our prospective clients, but it doesn't always work that way, thus we once had a client turn us down because he felt we were "more knowledgable than he was on SQF" and did not want a consultant showing him up - not my words, his.
And, we ourselves have turned down two prospective clients becuase we did not see a fit - one of them was doing something shady and would eventually get caught and the other was a micro-manager and we don't work that way.
Hope that helps.