I have been a management consultant for 10 years (fortunately managed to move just this year). My fee could be as high as 3k€ (4k$) per day, but this included not only my work but also the use of the company's resources, expert network and such.
I have worked in many assignments over these years. In some of them I was a real expert and could add to the client and in some others I did not have a clue about my client's business and had to learn on the go.
Usually the MC firm will take ore or several experts to the sales pitch and presentation and say that these experts will be available during the project. Make sure you get this experts to really work in the assignment as the real work will be done by very smart and hard working young guys that may or may not have relevant experience for your case.
Of course different firms may have different approaches. If you want specific advice PM me and we can discuss your situation.
On a side note I am now COO of an industrial company and could not be happier
