Hi,
Most of the cost is due to all the pre coating preparation of the paint.
Snow foam, rinse, Contact Wash, rinse, dry, fallout remover, rinse, dry, clay bar, rinse, dry, inspect with light, measure paint thickness, machine polish, panel wipe, light inspect, finish polish, inspect, panel wipe...then finally apply the coating of your choice to the paint.
Then consider the prep of the wheels (off the car), lights and glass with their coatings and it all adds up to a lot of time.
And whilst you're getting all that done, you may as well add in cleaning and protecting your engine bay, trim and tyres.
NB. The above is a proper job.
Or, you could do it all yourself. It isn't rocket science......honest.