I'm absolutely stunned by this. How dare they? This is totally unacceptable, for any reason. And, frankly, a complete breach of contract on their part. "I will pay you $10 for doing A, B, and C." then after you do A, B, and C, they think they can come back and say, "Oh, and D, E, and F too."??? And the pay will now be $9? After you've already done the shop?
Sorry, but if they did that to me, I would take the trouble and spend the $40 to sue them over it. Win or lose, it will make them think twice before pulling that kind of crap.
Totally unacceptable.
I think I'm going to shut them down again. Life is too short to put up with that kind of nonsense. There are too many honest companies to work for to go through all that for $10. If they want you to answer a question, they need to include it in the printout to start with.
Time to build a bigger bridge.