Written in java for minecraft this plugin was created to improve user gameplay. With close to 10k downloads and hundreds of active servers using it. You can checkout the old plugin page here

The RepairSign plugin provides easy to use repair locations to help improve the user experience from a general perspective. Before making the purchase you can check trough an invoice station how much its going to cost and get a detailed list of all prices for each item. You can even go as far as to change the default pricing for all items in the config. To repair or get estimate left click signs.

Repair sign   Repair sign   Repair sign