How do you break down your bids for customers? Do you break them down by doors/drawers, cases, units, finishing, or what? We go by base, upper, tall, doors/drawers, finishing, trim/miscellaneous, and install… but sometimes the less info you include, the easier it is to hide some misc. costs for some of those pain in the butt customers.
I make a detailed estimate listing all materials + 10%, and all hours per operation... Drawings, dressing lumber, cut to size, shaping, joinery, glue-up, sanding, finishing, wrap/delivery, installation, onsite extra work. I now give my clients the bottom line numbers only unless they ask for a breakdown, then I show the detailed estimate. Was told not to show too much information by a designer/client. Wasn't necessary. These days I don't work for pain in the butt clients at any price, except by accident. I miss the excitement of a confrontation, though! Good business can be so boring.
I prefer to show my clients everything (including the price), and have found that it cuts down on the number of phone calls I get asking what it would save to cut this, or that, or how much it would cost to add two more of this or that. It provides a menu for the client to choose what they want and what they do not want, with little or no interaction from me (I like less phone calls a lot).
This also builds trust between my company and my clients. They can clearly see what they will, and in many cases, what they will not get (i.e. light rail in a laundry room could have a line item with a zero quantity and zero cost if needed, which would remove the opportunity for a misunderstanding). They can clearly see that when a change is made, they are indeed only being charged for the additional items, or actually got a full credit for what was removed.
As far as hiding costs for problematic clients or jobsite conditions, that is taken care of in the markups themselves (the percentages that all of the material and labor content are marked up). As a matter of fact, I have one percentage available to me that is specifically for adding or subtracting to the job cost. If the builder insists on digging a moat around every house the day before we deliver, or stacking all the trim in the middle of the kitchen floor, he gets a little percentage added to all his estimates and proposals. On the other hand, if a builder seems to accommodate us, and always has clear access to the house at delivery, and keeps a clean jobsite, we can give him a small break on all his estimates and proposals.