Shocking . . . .
Clean the throttle body yourself. If you've got a manual transmission, the fluid change is literally a drain and fill. Not complicated. Etc.
What you really need to do is look at your owners manual and see what's recommended. If you don't want to do the work yourself, call around to some local shops you trust and ask them what they'll charge to do the same services. I bet it's half of what the dealer wants to charge.