They are only worth what someone is willing to pay. I know someone who wouldnt buy one of these cars for $5k. Some kid who has money and daddy isnt telling him how to spend it will make your car with more.
As for resale, the trade in wont take anything into account of the problems that models have if the dealership doesnt know. My dealer has no clue on these cars with the Fuel pump problems, and we have a 2007 we just took on trade for $17,200.00 Only 49k miles. If you wreck the car, do something stupid to the interior that you like, but the 41 year old woman buying your car next doesnt will affect the price greatly.
Dont sweat what your car will be worth, if your afraid of negative equity, pay off early or cash. You will not be making money on this car.