DO NOT pay $587 for a Mass Air Sensor!!!! Click above on buy parts above and enter your car info, the sensor is under 'air intake'. The sensor should be around $300. Phil (1-888-333-4642) will deliver it to you in 2 or 3 days. The car will run, maybe a bit rough, until you get the part without any damage. Replacing the sensor is a job that would take even a 10 year old child 10 minutes max. The fact that the dealer would have the audacity to charge you for installing it should be considered criminal. It's the easiest do it yourself job under the hood. You'll see tons of threads telling you where it is and how to replace it but in general it's as easy as replacing an air filter...
Based on what he's charging for that part, I'd say he's probably charging you double for the other problems.