5 hours is worth a couple hundred bucks IMO. You can’t pay the light bill with favors, but as long as he comes when you need him I wouldn’t charge him. I do think he should pay for the fuel, which he did, and he should offer to pay you for your time. It’s up to you whether or not you take it.
If your neighbor’s tractor breaks down in the road, you help him fix it for free. If a storm blows a tree down on his house, you help him get it cut off for free. If he is almost done picking his cotton and a hurricane is approaching, you take your picker and help him finish if you’re done with your cotton. BUT, if he’s custom baling for a customer and getting paid, then you should get paid as well.
For me it’s like this. If you need to borrow me or my hammer to fix your fence that’s fine. But you can’t borrow me or my hammer to fix a customers fence when you’re getting paid for it.
But when it’s your turn and you need help he should do the same for you. If not, then these guidelines don’t apply. I don’t mind doing a little extra, but it ain’t a one way street. I promise you can ask my neighbors and they will tell you that I have been as good or better to them, as they have been to me. That’s what makes good neighbors. That’s the way it used to be almost anywhere.