have no idea, didnt you ask for an approximation from the garage before having the work done; cost of parts, price an hour for labour, and how long they think it will take?
E.g i had my breaks done, i supplied the parts and asked a local specialist how much labour was and how long the job should take.
like the manifold - all in £500, I wouldnt get work done that i had no idea what i was going to be paying, its a coupe, you'll get ripped off any chance people get, thats why i took mine to a specialist, they sympathise with coupe owners generally.