Originally Posted by vanib
Brake fluid flush: $15 fluid, labour 1 hour
Transaxle and Reaf Diff fluid change: $15 fluid, labour 0.75 hours (for a diy home mechanic it might take 1.5 hours if you never did it before)
A busy mechanic would start draining the transaxle and rear diff (it is thick and needs time to drain), do the brake fluid flush and then fill up the transaxle and rear diff , all within 1.25 hours.
Check another local mechanic. You can even buy the 80w-90 (or 75W-90) gear lube and DOT3 brake fluid(to make sure it is fresh) for them and just pay labour.
I would pay at most $225 for this service at a non-dealer location. As you can see, this job is mostly labour.
If OP is getting the air filter & an oil change with the listed fluid changes, then $350 might not sound unreasonable. Fresh fluids are the life blood of the vehicle. Changing them too frequently may do bad things to your wallet, but only if you have no intention of keeping the car for a long time.
Don't forget, the power train warranty covers you up to 100,000 Km. A little good will (relationship) with the dealer goes a long way sometimes if a warranty issue pops up in the future . . . . . even though the Bumper-to-Bumper coverage is now over.