Traders?

[Fed]

I do not understand the subject matter of the two sides. If the trader bought the work because of how much he sold it did not matter the artist. If taken to implement, it must issue a receipt for the capture and percent markups. If someone did not take it, he (sorry, but the word hick can not think of anything). If you broke the percentage mark-ups and sold, it is also fortunate merchant, but did not cause the artist, who for the sum agreed.
The only problem-%overestimated the time, but work is not for sale. But this system is likely to deceive themselves, and do not see a major goal in this sophisticated.
   Ie I understand that the main problem - forgot to take a receipt?