$1911

I do a xmas sale at my school an idk how much I should sell them. I don't want them to be to cheap because they were very long to make, but usually students don't have a lot of money. I want to sell them around 5$-15$ , but everybody tell me that this is not enough. I did the patern #1 6 string wide, the #2 12 strings wide and the #28. Do you have any advices on the price?
Also, I used dollar store tread, so material isn't a problem.