Replying to How do i convince my parents?

okay so my parents want me to get a mazda 3s 5 speed car. it's an 05 with 20,000 miles. and it is pretty sick and a nice car. but the thing is it is $15,000!!!

now for that money i could buy a sick 04-05 WRX, maybe a little cheaper even really. sure it might have 50,000 miles instead. and i realize insurance would be more and premium gas.

it's not like they are paying for the entire car. maybe half, maybe. and my mom keeps telling me mazda's are more reliable blah blah blah you're not getting a WRX. she bases this solely on the fact my fuck up cousin got a brand new 08 STi and has wrecked it so much and it's probably cost his dad $100,000+ with the price of the car, repairs, and misc. trouble he got in involving the car.

HOW THE FUCK DO I CONVINCE HER?!