Edit Formulas in an Apple Numbers File

I need to have an existing Numbers file (Apple's version of Excel) edited. It is a pricing matrix used by sales representatives that contains a worksheet and several tabs that present the final price to the customer. We have had a price increase and just need someone to find the old prices in the formulas and edit them with the new prices. It is somewhat complicated, so it will take a little time to familiarize yourself with the file in order to understand the logic of the calculations. If this work is completed successfully, then I will have additional work similar to this.