It depends on your vehicle, check the maintenance schedule in your owners manual. A typical 30,000 mile service includes, radiator fluid flush, transmission fluid flush, brake inspection, ignition system check, possible spark plug replacement, wheel alignment, belts, lights and hose inspection.
A dealer will often charge more than other mechanics. Some may do the service for $200.00-$300.00, much less than $550.00 Call around and compare service and prices.
〉 Answered on Dec 26th, 2012 by Colleen McGee, Driving Instructor at Americas Driving School
Samu, without having the vehicle information, it is hard to know what is all needed as every vehicle will have different maintenance needs. Most 30,000 mile service intervals involve inspections, tire rotations, replacements of filters and other minor maintenance. I would get a second opinion from another ASE certified repair shop. It does sound a bit high, but depending on the car it could be right in line. Hope this helps!