100,000 miles used to be an automobile's life expectancy. They seem to be making them to last longer these days. European manufacturers like Volvo had been making extrememly durable cars for years, and when the Japanese became serious competitors in the tionernational market, they really upped the ante. I believe that Detroit had to finally come around, just to remain competitive, and nowadays ~ assuming routine maintenance ~ most cars ought to last well beyond one hundred thousand miles.

Of course, if six figures on the odometer is when you're ready to cut loose of one car and start anew with a newer one, so be it.

Regarding the question of whether or not to trade-in: it should be obvious that you can save money by selling the old car and then buying the new one without factoring in a trade-in allowance. But with the trade-in option, you're paying for convenience and liquidity, and many folks consider it worth the cost.

There's no way you can guarantee finding a buyer on the very day that is most convenient for you, and then taking the purchase price to a dealer to buy your replacement auto. You need enough cash in reserve to make your purchase without a trade-in and without the proceeds for your sale of the old car.

Plus which, trying to sell a car is a pain in the ass. Letting a dealer take it off your hands on the day you drive off the lot in your new(er) car is a convenience that many consider to be well worth the loss of however much more money they might have cleared by the sell-and-buy procedure.

Finally, if your old car is really old and worn out, the thousand-dollar credit given as a trade-in (that seems to be the minimum figure these days) may indeed be as much or even more than any private buyer would give you, even after you go to great efforts to sell, extending time and effort, fielding fruitless phone calls, buying classified advertising, etc.