I worked at a golf range; the owner was an electrician. He re-worked my house electrical and I worked for free at the golf range for the summer. Great arrangement.
When my kids were growing up, we lived in several places where (as a stay-at-home-mom) I was friendly with a few of the other moms in the neighborhood. When necessary, I just had to ask if one of them could watch my kids or they would ask if I could watch theirs for a few hours and occasionally, overnight. No payment was ever suggested or expected.
One neighbor, had me drive her daughter to her brownie meeting once a week because she had gotten a job and couldn't do it herself. I thought nothing much about it, that's just what we did to keep the community functioning. When the season was over, she surprised me by enrolling me in a tailoring class at her expense (she and I were avid sewers of our kids clothing). She did not have to do anything but I did enjoy the classes.