Mark-up is negotiable.
Subs have to be paid and so does the remodeler/GC/builder.

I would suggest you haggle by shopping contractors. Make AB.So.LUTE.LY certain you're pricing apples to apples. READ your contracts and bids.

Get bids for what you want, then decide between all you collect, what you can actually cut out, or change for perhaps a better design. What can be purchased separately, such as appliances off ebay, or trim from a reuse center (one 8' piece of cherry light rail is roughly $50 from Kraftmaid. I got 'em for $1.50 at H4H.), or things like that.

Shopping contractors gives you a leg to stand on. You can't haggle well with just one contractor, really, because all you ever get is change orders, you cutting out what you desire, and them working on another job that pays better when they can.

This, from a former GC's wife.
Please remember that the momentary adrenalin rush of "winning" a haggle can haunt you in 1/2-assed workmanship, quality of materials, and job frustration.

You create bid documents that list what you want, including cabinetry brands, granite names, sink names and models. faucet names and models, appliances models, and all other details that actually go into the kitchen. Then list the labor to be done, and be very specific about the details there as well. Then and only then are any bids you get actually meaningful to be able to compare. Once you understand the project enough to be able to do that, you will understand yourself where the project can be cut to bring it under your number. Or, you may understand that your budget number is too low for your expectations.

Asking a contractor to lower their bids when you aren't comparing apples to apples will lead to bigtime disappointment on your project as corners that you may not want cut will be cut.

Get bids. Get bids. Get bids. Then get more bids.

There are no set prices for labor. And you absolutely do not necessarily get what you pay for. Some GCs charge a fortune not because they are good but because their clientele are 1%-ers. Some charge low prices because they use idiots, and some charger reasonable prices because they are trying to build their businesses and have less overhead than renovation companies with fancy websites.

Get bids, and more bids. And yes, as hollysprings said, you need clear estimating sets first.

There is a nice kitchen site called "Kelly's Kitchen Sync" (http://www.kellyskitchensync.com/). She also wrote a very informative book that covers the topic of your question. Not surprisingly, her advice is similar to hollysprings: be careful how you compare.

Here is a link that might be useful: Kelly's Kitchen Sync book on Amazon

And don't forget, you'll also get bids from contractors who think *you're* a 1%-er :-)

Try not to splash on too much Eau du Cashflow before you meet with the contractors. This is not my first rodeo, but I have *never* received bids as high as the ones I am receiving on any project around my new house. This is crazy because this isn't a particularly affluent state/city, but I swear, these contractors want me to buy them a summer home in Tuscany.

I'm not sure that I would haggle, because on almost every job I've ever done, there's haggling within the transaction - after it's underway. And the homeowner is almost always the loser. I wouldn't want to start out as the loser. When you're betting, the house (contractor) never loses.

Thank you all for your input.

I didn't mention this in my original post, and I might have phrased the question poorly. I already have about half a dozen bids, and I'm not really worried about the cost of the appliances, faucets, and flooring. All the contractors I'm working with either has an allowance for them or I'm responsible for buying them separately. Since I can do all the comparison shopping I want for these things, I feel pretty good about that chunk of the project.

The challenge is the cabinetry and overall labor. I'm not wedded to a particular brand of cabinetry or working from a specific design. We decided against hiring someone to come up with a design separately. We figured that so many places offered to do them for free, why would we pay to have one drawn up.

The result of course is that each kitchen company has their own cabinet line and own design. Don't get me wrong, I'm not talking about radically different designs. For the most part, they have the same general layout, but there are certain nuances that are unique to each one. So it's not a situation where I am comparing one kitchen company offering 24 Wellborn cabinets with another company with the same 24 Wellborn cabinets in their design.

Right now, we're leaning toward one particular company, because they have a good track record, a nice plan, and we like working with its designer. I get that businesses exist to make money. My goal is not to squeeze every possible dime out of the deal in my favor or to find the cheapest bid. Like so many of you pointed out, making a contractor feel underpaid is one way to ensure he cuts corners. I don't want that. What I am looking for is a way to engage them in this discussion, without them automatically coming back to me to cut scope to lower the price.

Speaking as a kitchen designer who often presents installation quotes, why don't you just tell them that you have gotten many bids, really like their company but that they are on the high end. What can they do to sweeten the deal? Don't make it adversarial but the beginning of a team approach. I'm betting they will work with you to get the project. If you really trust them and they won't lower their price you might decide to move ahead with them anyway. There are hundreds of examples on this website of people who get into the middle of a project and then are manipulated by unscrupulous contractors. It has really opened my eyes to how vulnerable client's are when they put their trust in me any my contractors. I'm lucky to work with tradespeople who really do put the client first and will do all it takes to please them. They are the greatest but even so, they will often find a way to take off a little money to secure a project. My advice is to ask to see actual projects, find out if any subs were used and request (demand) the same people work on your project. It's good to save money but better to have confidence that you are entrusting your home to the right people.

but does this mean labor is not negotiable?

You can lower labor costs by using inexperienced workers. Do you really want the contractor to do that?

It means higher supervision cost and slower work to keep the quality up.

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Here's the engineering slogan that applies: Good, fast, cheap ... pick TWO.