I invented an automated shop that a customer puts a set amount of a resource into a hopper and the machine counts out and gives the customer what they purchased. The downside is changing the price requires much of the machine to be rebuilt so I need to figure out some of the prices before I build a shop.
What would you be willing to pay in diamonds for:
Diamond horse armor
Gold horse armor
Iron horse armor
EFF 5 book
Silk touch book
Fortune 3 book
Once I determine a fair value I plan on opening a shop and will consider showing people how to make the machine themselves.