Price per catagory - you could if you want. I think it depends on the size of the job and the customer (sometimes, like I mentioned before, it encourages the customer to pick and choose what aspects of the project you will be handling) for instance: Your proposal, "Demo - $7,000" --- Your potential customer, " Oh I have a brother inlaw that can do the Demo for a bag of crack." But you can do everything else and you can start dropping your tools and supplies off ASAP. CRACKHEAD BROTHER INLAW + YOUR TOOLS =
Sorry, I don't know what came over me, I never had that happen to me or anything.

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Seriously though some customers do like to see where the money is going. How ever you are going to do it put EVERYTHING in writing -- details, details, details...
In my experience when the HO tries to be the GC everything gets dragged out that's why I'm kinda against them "handling" parts of the project.
I just reread your last post. YES always write in allowances. And I break that down to labor vs. material.
The cost of labor is the same for a $2.00 tile as it is for a $20.00 tile.