The problem isn't that they accepted, it's that you didn't quote a price high enough to offset the headaches they caused. If you had, you would have been happy!
That's what I'm saying, if you had gone with a price that would make it worth your time instead of a price you thought they'd decline, it would be worthwhile. I see how you can fall into that trap, though.
Then it wasn't enough :p We'll never stop arguing, but consider this: Wouldn't you be happy doing it for a billion dollars? Somewhere between that and what you got is your "happiness threshold", it's just that it's more than what you got now.
Unless you wouldn't have been happy with any amount of money, in which case I assume your client was the third Reich!
