I recently made the mistake of getting tires through my local dealer. I've had trouble with them before, so I was exceedingly clear that I wanted a fair deal and all charges known up front.
They gave me a fair price up front and told me there would be no difference in price between bringing in the wheels or the whole bike, so I brought it down, came back to pick it up, and funny thing, I was charged for 2 hours of labor at $85/hr for the installation.
For reference. That dealer is Libby's in New Haven, CT and I would reccomend that no one ever patronize them unless they're comfortable with their wallet, bike and sanity being molested.