@rbreich
Mechanic:
That'll be $500 please

Customer:
But all you did to fix it was hit the engine with a hammer, took you no more than 1 minute!

Mechanic:
Exactly, I charge $120/hour + the service fee

Customer:
So I only owe you $2 then!

Mechanic:
Yes, for the labor; and a $498 service fee for knowing where & how to hit with the hammer.