Inventory Settings control two important shop-wide behaviors: how negative stock is handled and how labor is billed.

Go to Settings > Inventory.

Allow Negative Inventory

  • Enabled (recommended): when an invoice would push stock below zero, the employee sees a confirmation dialog and can proceed. Negative stock is recorded and visible on the product.
  • Disabled: the system blocks any transaction that would result in negative stock. Invoices can't post, return orders can't be created.

Most shops enable this - real life produces edge cases (vendor sent extras, item miscounted) where blocking sales would be worse than recording a temporary negative.

Labor Billing Mode

  • Flat Rate: each labor line bills the labor amount you enter regardless of clocked time
  • Hourly: labor amount is entered as hours times rate per labor line on the invoice. No relationship to time-clock data; you type the hours when you bill the line.

Flat rate is the default for most car-audio shops. Hourly makes sense for diagnostics, custom fab, or anywhere the work isn't standardized.