One of the more common functions that is available in many ecommerce solutions is the ability to show product quantities.  The following Opencart 1.5 tutorial will walk you through setting up the option to enable the display of product quantities.

How to Enable the Display of Stock Quantities in OpenCart 1.5

1. Login to the Administration Dashboard as an Administrator
2. Hover over the menu bar where it says SYSTEM and then click on SETTINGS in the drop-down menu
3. Select the STORE that you wish to edit and then click on EDIT on the far right to proceed
4. Click on the TAB that says OPTION, then scroll down until you see the option labeled DISPLAY STOCK as shown below:
   
5. Select YES to enable the option to display stock or NO to disable the display of stock quantity.
6. Select the BLUE button in the top right save the option you have selected.

The Display Products option is an important item to enable if possible so that your customers will be able to determine when the product is available.