I can't think of anything, most especially something in the way of what would be considered "service," rather than "product," that has a more widely varying price than a paint job. What you are buying when you buy a paint job is labor and skill.
Just because you are paying more, does not always mean you are getting more skill OR more labor. The price range runs the gamut.
You are on the right track in thinking of stripping the trim from the car yourself. Keep in mind, though, that much of the trim on an MB is such that you have to know where the tabs are and just how to release them to keep from destroying the trim. If you are taking it to a shop that has never stripped MB trim, you have just as much chance of doing it without destroying it as they do. That said, you probably have a better chance of preserving the trim because it is your car. Most shops probably actually prefer that you remove trim. Their talent and skill is in sanding, preparing and painting.
Overspray, orangepeel or runs will probably be no problem with a quality shop. These are the problems you run into with the cheap and quick enamel jobs done by the national chains. Most any decent shop has someone that can properly "shoot" the paint, even on their worst day. 90% of the quality of a paintjob is determined by the preparation. Probably 90% of the labor hours you pay for are also for preparation. The most common mistake by an amateur or beginning painter is thinking that the paint will cover up whatever flaws they have in the preparation. Just the opposite occurs, the sanding or bodywork flaws are "brought out" by the paint. The good news is that a decent painter will probably refuse to shoot paint over an improperly prepared surface.
You usually can spot an amateur paint job by the craters. Craters are the low spots made by feather edging chips away with sandpaper. When you do this, you should evenly distribute the sanding over a large area, or fill the chip rather than sanding it away.
I would expect that a decent paint job would cost a minimum of $2,000. I doubt that you will get much from your Benz dealer besides the offer of a high rate. You need to talk to the car enthusiasts in your area to find a quality paint shop. It doesn't matter what kind of car they are enthusiastic about. Talk to the street rodders, the Mustang club, the Corvette club, etc.