What I do for a living.

[counterfiend]

Well you can wash it all you want, its a matter of how you wash the car?
Do you use 1 bucket, with just a bit of soap? Do you use just soap on a mitt and a water hose?

The proper most effective way of keeping swirls and scratch's off the paint is with a 2 bucket method with a grit guard.
Basically you have 1 bucket with just clean water. And 1 bucket with soapy water (VERY SOAPY, at least 1oz of soap per gallon, because its acting like a lubricant). And the grit guard goes in the bottom of the clean water bucket.
So you get your soapy mitt, you wash an area, and then you rinse the mitt out in the clean water bucket, scrubbing the mitt against the grit guard. This helps to work dirt and anything off the mitt into the clean water bucket, so you can then go back to the soapy water, rinse repeat.

And price wise for something like that all depends on how the car was to begin with. Anywhere from 250-300 for a car that doesnt need too much work to be perfect which is just a good deep polish. And 500 up for a car that needs buffing. The more work is done, and the longer it takes obviously the price goes up.