I have a client.

We agreed to a set fee (more or less tentatively, nothing in writing) that was below what I would normally charge - I guessed the project was worth $2000, and because they were a friend of a friend, and I was interested in developing the technology I spoke to him about (and retaining the copyright), I agreed to do so for $1000.

That was several months ago, and his project was far more complicated than initially envisioned. Rather than the 20-60 hours I suspected the project would take, I'd wager it has risen to be about 200 hours. Every time I think it's done, something else pops up. At this point it really does actually seem to be done - we've tested it in real-time, and it works for new users.

Now, we have nothing in writing, and he more or less seems like a square guy. Understanding that I should in the future not probably do freelancing this way (I'm new to entrepreneurship), I'd like to renegotiate the fee.

I don't really want a, "wow, that was dumb!" or anything like that - just pure actionable advice on how to renegotiate a fee, or push for higher payment - perhaps even a link to information on how professionals do this.

I'd prefer to aim for around 3000-5000 as payment.