You can flush your own power steering fluid. Not knocking the dealer for trying to make a buck - but you can save $$$.
PS systems have a pressure line and a return line.
Go to ->
http://www.utoyot8.com
and provide your vehicles info - yr/make/model/etc
Look for -> Power Steering Tube
Sketch of your vehicles PS system there. Locate the return line/hose.
Buy a qt of reg. ps fluid at any auto parts store.
With car off - remove ps return line and point it downwards. You'll likely need to find a length of some kind of tubing to put into the end of the ret. line hose so you can get it all the way down where you'll stick it into a drain pan you've placed underneath the car.
Have some start car and gently rock steering wheel from side to side. While this is going on - add ps fluid to ps reservoir. Don't let the reservoir run dry. After the better part of a qt. has passed thru - shut off motor - reconnect ret. hose and top off fluid.
You do all this yourself for the cost of a qt of ps fluid.
Some cars actually use Dexron for PS fluid and some(Honda) have proprietray PS fluid. Never seen a Toyota that used Dexron - even though the owners manual may say it does. All 3 of the Toyotas I service - 2004 - 2007 indicate Dexron for PS fluid in owners manual. All 3 have golden colored PS fluid which is not the color of Dexron. I use plain ole PS fluid. Whatever is on the shelf.
If your PS fluid is reddish-purple - tranny fluid color - then you use Dexron in the PS unit. If its more of a golden type color(what it is when fresh) - you use reg. PS fluid unless manual says to use mfg-provided PS fluid.