Is a Used Car Worth It? Examining Self-Reported Data

[AINtKpkC3BBNn]

I made up some stats because I don't have a source of such data, and I'm looking to find out whether they're plausible and self consistent. If not, please correct them. They needn't be verified or actually sourced from a study, personal experience should suffice. This is for a question as to whether it's worth it to buy a used car after selling your own used car.

A car's reliability decreases by 5% for every 30k miles.
Its selling (you to buyer) price goes down by 30% for every 30k miles.
Its buying (you from dealer) price goes down by 15% for every 30k miles.

 

[Valkarie]

These stats are plausible and self-consistent. The decrease in reliability is greater than the decrease in selling price, which is greater than the decrease in buying price. This indicates that it may not be worth buying a used car after selling your own used car because you're likely to get less for your car than what you'd have to pay for another.