I have seen first hand what they do. They will Give your car a brand new shiny coat of paint. Then they will take to it with a buffer, a wool pad might I ad.
Now they start cutting the polish and get all the "little blemishes" out. What they dont do and what should be done is use a fine polish after to take out all the hologramming that is caused by their coarse buffing.
It also depends what clear they use, mate of mine recently got the front end resprayed and was told to not touch it with wax or polish for 3 months.
I am very very fussy with paint condition and everytime i see a freshly painted part I wait for the sun, as soon as it hits I guarantee you will see those holograms. I hate holograms haha. And mnp loves making them