If you give them it for nothing, and they like it, they will baulk at paying for the next one. As DavidRM said " If you don't put a price tag on your work, on one else will." Which is just as good a way of saying: "I'm giving you this for free. It's not worth paying for." How often have you really valued what you've been given for free? So why should those readers? However high the price you ask for your work, it will never be adequate financial recompense for all the hours you put in. Unless you're a huge name. Most of us aren't and we accept that. But don't devalue yourself.
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