Yeh, so to help you with this, tell us exactly what is wrong and what the dealer said it was.
I'm sure we can come up with a writeup or a how-to type thing to avert paying 800 bones for some O-rings. I had an HPOP Oring blow out on me and the ford dealer told me it would be at least 600 bucks to repair. I got their "kit" for $27 bucks and repaired it myself. Afterwards, I found I could have gone to any hydraulic shop and gotten the Orings for $0.25 each and some locktite for about 3 bucks.
I'm sure we can assist in lowering your expenses