Asyria, in all fairness, if it's using your mats, not the crafter's, then the crafter is completely in the wrong to try to bring up the price for the product you commissioned them to make, if it's with their mats, they can feel free to charge what they want, that's not the issue at hand though, the issue is if they are utilizing your mats to make something you commissioned them to make, there is absolutely everything wrong with going back on a trade agreement and taking someone else's money and materials and then trying to make them pay more for you basically getting lucky while crafting.
EDIT: Freyar, unless you paid them before hand, the loss would simply be the mats, in which case, it sucks, but you took the risk knowing the synth could fail, it's the same as doing it yourself, only difference being that if it succeeds you pay the person crafting it for you.
EDIT: Freyar, unless you paid them before hand, the loss would simply be the mats, in which case, it sucks, but you took the risk knowing the synth could fail, it's the same as doing it yourself, only difference being that if it succeeds you pay the person crafting it for you.