I am sure that very few would do this but some people may actually want to personalize a head or a set with something unique and would actually pay that ammount.
Some rules should be implemented.
And i am not very sure how the payment should be done...since u probably dont want to waste peoples time and don't pay in the end. So make a very exact demand, get aproved, pay and then work with the person who will make it. Maybe.
Or every now and then (3 months) relise a random item and auction start auction for 15 days. Highest bid wins a unique item and gets to write the description...idk