I bought my 1997 ES300 as a certified pre-owned in April 2000 with 42,000 miles on it...16 years later it still runs great with 212,000+ miles on it...I will replace it next year so Im debating whether to replace the timing belt and water pump or not... I religiously change the oil and rotate / balance the tires every 5000 miles.
Btw I never sell or trade in my cars but give them away to somebody who really needs a car so Ill probably go ahead and do the timing belt and water pump.