Either I don't understand your point, or there is no doubt it sounds great to you.
To be sure: I provide the mats for all attempts, and then have to pay for the item?? Seriously?
The way i see it, I would give you a tip for... you know, being cool and keeping an eye on your companions, and for taking the time to research the eschematic if that is the case.
Marketing here is very simple: if you have no costs for making the item (I provide all mats), the only think you can charge for is providing the service.
The effort, time, and credits invested (by you) in being able to provide that service is something you should be looking to get back by adding all profits obtained in the long run. Not for every time you provide the service.
Your system, as a customer, seems highly unacceptable to me. All due respect.
Sorry, my economics English is very poor, hope I explained myself
It's a game dude, not a job. I play to have fun. Call me crazy I guess.