Situation: Customer owns several convenience stores. You have already done two stores successfully and have quotes in for several more. After dealing with the seat-of-the-pants owner on the first two, all of a sudden the controller is getting involved asking for breakout of parts and labor per store. Previously you have only provided minimal line item detail and no line item prices, just the total, in true contractor style.

Since you have done the two stores, you know that they are real, but at the same time, by the questions by asked by the controller, you feel you are being shopped.

What's the best thing to say to avoid breaking out the quote while not screwing the deal?