Your Bid to Set Up the Computer System at Evergreen

Essay

Your bid to set up the computer system at Evergreen, a small local business, was accepted. Today you found out that the software that Evergreen's systems require just had a price increase, so your bid will need to increase to reflect this change.
-As you plan your message to notify Evergreen of the increase, you consider not telling them the reason for it, as you don't think they need to be bothered with the technical details. Why might this backfire on you? What might you do in your message to soften the bad news?