I think you should ignore some of the negativity around you, like people saying you’re “stupid” or “being used”. If I were rich, I would spend my time doing ex

I think you should ignore some of the negativity around you, like people saying you’re “stupid” or “being used”. If I were rich, I would spend my time doing exactly what you’re doing: having fun working on cool software, with interesting people, and contributing to projects that get used in the real world. And I wouldn’t spend too much time worrying about the messy side of handing money and invoices. Of course, we all need to eat, and so you should work on learning how to handle the business side better. It can will be painful and frustrating at times, but some of the other commenters have great suggestions, so I don’t have anything to add. But don’t be negative about what you’ve done so far! It sounds like you’re doing great at the most important parts of the job, which is finding projects and having the skills to pull them off. Like Paul Graham says, it’s easier teach business to coders, than to teach coding to businessmen.