'97 Miata w 66k miles.
or so the wife thinks.
I'm planning on keeping the Miata at least another year after buying the BRZ, then I will see depending on how much use the Miata gets, my financial position, and market conditions.
I also have a WRX wagon w/ 100k miles that I plan on keeping.
FWIW - if you don't have experience trading a car in to a dealer, let me tell you how it works: they take the trade in value for your car, then subtract est costs for items the car needs. You end up with a hassle free transaction (usually*) but very little cash in your pocket. If you have a CarMax near you - take it there for a quote. They will buy your car even if you don't buy theirs. They pay closer to trade in value, depending on the car/mileage/condition.
CarMax buys your car with the intention of selling it, whereas the dealer typically dumps it at auction - hence their low offer bc they don't want to lose money on it.
On the other hand, while selling privately can get you more money, it's also more work, and involves strangers who may or may not drive well (or even have insurance) getting behind the wheel of your car. If your car is not paid off, you have the added layer of arranging the payoff and release of lien with the buyer's funds.