Ok, a few things that I'm not sure if anyone mentioned, as I skimmed the last page or so.
First off, it's important that the crafter and the customer know what happens if the crafter HQs, NQs, or breaks. Nothing worse than getting into a dispute because the terms of the contract weren't stated ahead of time.
Now, here's several different payment methods for someone asking a crafter to make something:
-Lucky roll:
The customer gets all ingredients and gives them to the crafter, plus a comission fee. The crafter synths it and gives the result to the customer, regardless of the outcome. The customer pays the exact same ammount if it's a HQ, NQ, or break. The comission fee should be based on the chance of getting a HQ and how much profit a HQ is; in other words, if the crafter does nothing but "lucky roll" contracted synths, he or she should make profit comparable to what he or she would make from simply making that item several times and selling on the AH.
Philosophy: The customer is risking his money on the synth, instead of the crafter risking it, so he reaps the rewards of a HQ and feels the woe of a bad break. Essentially, the crafter is acting as a slot machine for the customer, and could offer a big payout or absolutely nothing.
-Lucky roll w/ insurance:
Similar to lucky roll, but the comission fee is higher and if the synth is a break, the crafter gets all needed materials again and attempts the synth again.
Philosophy: Similar to lucky roll, but the customer always gets something and doesn't lose everything to a break. Since this is more expensive for the crafter, the comission fee is raised to compensate.
-Guaranteed HQ:
The crafter keeps making the item until a HQ is made, then sell that to the customer at a price matching the AH. This is usually done ahead of time and then the HQ is advertized somewhere (such as on the AH board here), and is usually done with signed items as they can't be sold on the AH.
Philosophy: Usually, the crafter makes a signed HQ item and sells it to a player directly instead of going through the AH.
-Guaranteed NQ:
The crafter simply make a NQ version of the item and sells it to the customer for a price close to the AH price. Usually done ahead of time and done with signed items, as you can't sell them on the AH.
Philosophy: Same as Guaranteed HQ.
-Risked synth:
The customer gives all items and possibly a comission fee to the crafter. The crafter makes the item and simply gives it to the customer if it's a NQ, or charges a portion of the HQ's sale price if it's a HQ. The comission fee, if any, is lower than lucky roll, but the cost of getting the HQ is raised to compensate. No compensation is made for a break.
Philosophy: The crafter isn't making much of a profit, if any, from a NQ, so they charge more for HQs to compensate.
-Risked synth w/ insurance:
Similar to risked synth, but the crafter compensates the customer if there's a break. The comission fee is raised to reflect this.
Philosophy: Similar to risked synth, but the customer still gets the item if the first synth was a break.
Hopefully, everyone can find a payment method that suits how they want to pay the crafter, or get paid for being the crafter.