[twblalock]

Your car won't last forever. You will need to buy another car sometime. Money you spend on repairing your current car could be put toward purchasing the next one.

Let's say a transmission replacement costs $1000 for your car (that's low, by the way). You could sell your car now for $1500 and buy a another one, or you can spend $1000 keeping it on the road for a few more years, sell it for less than it is worth now, and then buy another one. That $1000 was wasted since you had to buy another car anyway -- you would have saved that $1000 if you bought the replacement car sooner.

[dual_basis]

How are you getting $1500 for a car that needs $1000 worth of transmission work?

That only works if you can see into the future and know that you will need transmission work soon, and then it requires you to find a buyer who doesn't share that opinion. Essentially, you have to screw someone over.

Otherwise, if the transmission is already broken, the situation is that you either pay $1000 and get a working car (ie. repair the transmission) or sell your car for $500 and then buy a new one.

[kop316]

I agree, but going back to your analogy, I would rather spend the $1000 and not have a car payment for another few years (assuming a $200 for a year, that's $2400 I'm not paying).

My bigger worry is if I get into an accident, the value of the car is so low that the insurance will total it, and now I'm stuck with buying a new car.