All my dogs I got for free. Either got them out of a litter, a rescue from a shelter, or take in as a stray. Of course, they end up costing big money once you get them! But worth every penny.
My current dog, a border collie/australian shepherd mix, was abandoned in the woods. When I found the puppy, it looked to be about 12 weeks old and was covered in ticks. It must have just been abandoned as I'm sure the coyotes would have gotten to her eventually. We bonded right away although even today (four years later), she has trouble with strangers. This dog keeps me in good shape as she requires several miles of walking every day.
We paid $500 for our “show” GS way back when, which regular people thought was crazy - and she was worth 10x that. A truly Great Dog, though worthless in the show ring. But she was so much better than any dog I have ever, ever even heard of; I was proud of her inherently 99% perfect character and behavior. I wouldn’t trade her for anything. But ONLY her I wouldn’t trade. The other dogs haven’t been worth what she was, and that’s an honest unemotional assessment.