Over the years people would periodically turn up out of the blue and ask 'Can you saw (or plane) some wood for me?' Of course it's a flipping nuisance to do but you want to help people, and the social interaction can be amusing. Anyway my first reaction is always that I want to see the wood, which often baffles them a bit. Then you do a quick assessment for possible grit, metallic foreign bodies, etc, whilst working out the strategy - eg put an old blade in the bandsaw or circular, etc. Sometimes it's a straightforward 'No'. They always look crestfallen then, but I explain about precious cutting edges and that allows some understanding. Other times, out comes the wire brush ...
One chap is clutching a couple of feet of old floorboard that has a pencil line at least 2mm thick along it. Can you saw this to my line? Cursory inspection - 'Yes, I can do that.' 'When shall I come back?' 'I'll do it now.' At the sawbench I turn and say 'which is the waste side of the line?', at which he gazes at me, puzzled. Waste side isn't in his terminology. He just wants me to saw down the line ... happy days!
Then comes the finale - 'What do I owe you?'. If it's been less than 10 minutes I usually say 'Oh that's ok, nothing' and they go off beaming. One woman came back half an hour later with a bottle of white wine as thank-you. I don't like white wine, but worse than that it still had the price sticker on it - £2.99.
More than 10 mins I would normally charge pro rata at a lenient rate. Planed some hardwood that someone had brought whilst he waited, told him the price and with a po-face he said 'That's a lot!'. But he stumped up & off he went. Luckily he never came back, because I'd have refused him.
Spread a little light and the world swings more sweetly ...