Also dont be afraid to haggle a little bit.
Ask them if they would do it for like 350 for instance and say you would pay in cash.
I bet they would say ok, they are just trying to see if you will bite on the super high price like alot of their customers probably do.
I go to a place called mexico mufflers, and they told my bro 300 to install springs. I got them down to 100 bucks lol although it is hard to communicate.