About $400 - $550 for pads and rotors. It is a bad sign if it needs pads and rotors after 4 years - the pads on both of our two 2002 Prius look literally like new after 9 years.
The fuel tank capacity is 11.9 gallons, so a fill-up of a completely empty tank is right at $48 at $4.00 per gallon. As with all modern cars it is not a good idea to run it below 1/4 tank (have mercy on the fuel pump!) so $35 is a more common fill-up. If gas hits $5 per gallon it will take almost $60 if dry and $45 typically.
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