Enable inventory You can enable the inventory option for a product and enter the available stock. Neartail automatically keeps track of the product orders and updates the available stock. When the stock becomes zero, the product is marked as sold out. Please note that inventory feature is not supported if you have delete the default quantity/weight options for a product to enable the +- spinner widget. Enable inventory for products https://neartail.com/order-form/add-products-with-limited-stock.html How it works? When the user clicks on the add to button for a product, Neartail checks the available stock and displays the quantity options accordingly. For example, you have added a product with 1, 2, 3, 4, 5, 6 as quantity options. When the user clicks on the add to cart for this product, it will show these quantity options 1, 2, 3, 4, 5, 6 for selection. If the available stock for this product is only 3, then when the user clicks on the add to cart for this product, it will only show 1, 2, 3 as quantity options for selection. What happens when multiple users place the order at the same time? The inventory is checked when the users are adding the products to the cart. If two users click on the add to cart for this product at the same time, then it will display 1, 2, 3 as the default quantity options for both the users. If one of the user selects 1 and the other user selects 3 and submits the order, their order will be placed successfully. The product will then be marked as out of stock with available stock quantity as -1. If after adding the products to cart, the user clicks on the add to cart for the product to update the quantity, then Neartail will check the available inventory and show the updated quantity options. When the users opened the form, it would have displayed the quantity selection options based on available stock at that time. If multiple users opened the form at the same time and tried to submit, they would have been able to place the order. Simply put, the quantity options for a product are displayed based on the available stock at the time when the user clicks on the add to cart and the inventory for a product is updated when the order is placed.