We're going through the same change at our company. Our hours are all estimated which would seem great right? Well, yes and no. My boss and our one salesman like to use this category in our contracts called allowances! Which I precieve as a lack of ability or knowledge or time to figure out what actually goes into an install to make it work. Not to mention the billing issues associated when the installer, who already has a million things to remember, has to itemize everything used on the job site. I would love to have stuff bid out again, so that the salesman/designer had to do there job instead of the installer doing it for them. If the job runs over, it's a poorly planned out design and they really don't know your abilities as an istaller.