The reserve system is a nice feature to help convert your users to paying clients!
Using the reserve system allows you to enable a reserve form on your inventory item pages. A user can fill in this reserve form and they will then be allowed to pick it up at a later time. They get an email confirmation and the administrator also gets a confirmation email. In addition, the quantity decreases by the reserve amount automatically in the system. For more information, please refer to the Reserve Setting section in the Quick Start Guide.