Repairing unique items also usually results in payment
Yes, when your repairing unique items, the noble need give the item to advy first.
After advy finish repair, advy give back the unique item to noble and noble has option to pay or not to pay.
Another option mentioned in post earlier, is advy joining the guild.
The amount of debts owed, can be increased according to the guild rank.
My last advy have the fortune of joining an advy guild, dedicated to combat all creatures of darkness