How much do dealerships and/or independents charge for a brake fluid change? If the price is too high, I may choose to do this myself -- is this difficult with the LS430? I have some experience with brake fluid flushes, but only on older, non-ABS cars.

Any advice would be appreciated.

 

Get a Motive kit and do it yourself. You need to get the univeral kit for Lexus and it would fit almost all other brands as well.
You can bleed them without removing the wheels, just jack the car up and there is only one bleed hole per corner(caliper). Took me about 30 min. to do mine. Hope it help, good luck.