There's an old adage that the rate a consultant charges has to feed two additional support people back in the back office. If you're a one-person shop, that tripling of fees goes to support bench time, organizational expenses, and the time spent doing non-consulting work (like working with Quickbooks).

I found this link not long ago that includes some very intelligent suggestions for would-be consultants for how to set their rates. What's great about this article is that it works today for established consultancies as well. A standard consultant that makes $250/hour rarely sees more than $50 to $70 of that rate, with the rest going to the consultancy. You'll also regularly see consultancies trying to move you towards monthly rates, which they call "annuity income". With monthly rates, you pay the same no matter how many services of theirs you consume. These rate structures are a bet on both your parts, each hoping that you get the right amount of profit out of the agreement.

Check out the article here. If you've ever engaged with a consultant, you'll want to know how their internal accounting works if you're to get the best deal.