Ah, OK. Because I was gonna say, if your car is in excellent shape, and it's paid for, the most economical thing is to hang on to it?

But OK, I see your point now.
Well, if you sell to private parties, you generally make more than if you trade in. It's also more of a hassle and it can take longer to sell so you have to be patient with that.
If it's that important to you to have an auto, but you don't want to spend too much money right now, maybe you could get a "gently used" car from a dealership under their certified program? You will find some cars at the end of their lease that someone traded in to get the next brand new stuff off the lot. I got my Yaris that way. It's a great car, works like clockwork, knock on wood. The original owner purchased another Yaris LB, but with a 4 door instead of 2 (more convenient for her kids, I think she had a couple of small kids) so I got her car.
Trading in has one advantage: it's fast and it's done when you drive off the lot. No spending all your Saturday afternoons for the next 2 months giving test drive to people who may or may not know how to drive

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