The Options & Attributes Stock addon extends the standard PhoenixCart inventory system by adding flexible stock control for individual product options and attributes. It is designed for products where a single option (such as ring size, chain length, or clothing size) requires its own inventory management.
Features

Four Stock Tracking Modes
Untracked – Option and attribute stock is not monitored.
Product Attribute Tracking – Stock is managed individually for each product attribute. The attribute values are linked to their corresponding entries on the Product Attributes page.
Attribute Value Tracking – Stock is managed by the attribute value itself, allowing the same value to be shared across multiple products. Values are linked to the Product Attributes page.
Referenced Product Tracking – Stock is managed by a separate product. Each attribute value is linked to a product in Categories/Products, allowing multiple products to share the same inventory.
Automatic Stock Validation
Prevents customers from purchasing attribute values that are out of stock.
Keeps inventory accurate throughout the shopping and checkout process.
Includes a Pi Layout module which replaces the PhoenixCart core Options & Attributes module
Optional setting to show attributes in drop-down menus or radio button groups.
Optional setting to show out-of-stock attributes.
Optional setting to show available attribute stock.
Optional setting to disable zero-stock attributes.
Optional setting for options attributes image support.
Optional setting for options attributes weight support.
Flexible Inventory Management
Choose the most appropriate tracking method for each product option.
Ideal for managing sizes, lengths, dimensions, or similar single-option inventories.

Typical Use Cases

The Options & Attributes Stock addon is suitable for products where a specific option requires independent inventory management.
Examples

Jewellery
A sterling silver ring can use Product Attribute Tracking for available ring sizes, allowing each size to have its own stock level.
Different stone types can be created as separate products, each with its own images, pricing, and inventory. These products can then be displayed using the PhoenixCart Related Products Addon and its integrated layout module.
A pendant can use Attribute Value Tracking for additional options such as different silver chain types (for example, snake chain, box chain, or other chain styles) when these chains are only offered as selectable options and their stock is managed independently from the pendant.
If the same chains are also sold separately as products, Referenced Product Tracking can be used instead, linking the pendant's chain options directly to the corresponding chain products. This allows the same inventory to be shared between pendant selections and standalone chain sales.
Household Appliances
A kitchen fume extractor can use Attribute Value Tracking for optional mounting or installation kits.
The same kit values can be used across different appliance products while maintaining their own stock levels, without requiring each kit to be created as a separate product.
Footwear
Shoes can use Product Attribute Tracking for available shoe sizes, ensuring that each size has its own inventory level.
Different colours or models can be managed as separate products when they require individual images, prices, or stock control.

Admin Stock Report Page

The Options & Attributes Stock Report provides a technical overview of product stock and tracked option/attribute stock levels.
Features

Optional Categories and Manufacturer filter.
Displays the current stock quantity of each product.
Highlights products and attribute stock levels below the configured Stock Re-order Level in Admin → Configuration → Stock.
Shows stock-controlled option and attribute entries linked to their corresponding stock source:
Product Attribute Tracking – Stock is controlled by the product attribute, with values linked to the corresponding entries on the Product Attributes page.
Attribute Value Tracking – Stock is controlled by the attribute value, with values linked to the corresponding entries on the Product Attributes page.
Referenced Product Tracking – Stock is controlled by the referenced product, with values linked to the corresponding product entries on the Categories/Products page.
Untracked – Option/attribute stock is not tracked.
Groups product stock and option/attribute stock information in a single overview.
Provides a direct view of the stock source used for each tracked option or attribute.

Optional Support

Attributes_weight
Options Images
Wholesale Lite
Wholesale Pro
Ajax Attributes Manager

Customer engagement is key to a successful shop - reminding customers of your shop and products is an excellent way to get them to return and have another look. It is so much easier to have an existing customer return to your shop than it is to find a new customer.

This Scheduler Module for the Queued Emails system adds emails to the Queue (when any customer purchases any item) based on two parameters;

a. is the live stock of the purchased product(s) equal to or less than the default setting of 5 (but greater than zero in stock)
b. does the purchased product(s) have any customers subscribed to notifications

If the answer is yes, emails are scheduled to all customers who are subscribed to notifications about the product(s).

Setting up the "Stock Notification" module takes no more than 2 minutes;

1. Upload new file
2. Write your Email, utilising the inbuilt "merge tags".

If the price of this addon does not suit your business, contact me anyway. I'm sure we can come up with a good deal that suits each other. Prices are not set in stone.

If you are on a version of Phoenix from 1.0.8.5 to 1.0.9.5, this addon is still useable so long as you install the Queued Emails foundation system found here which is a backported version of the 1.0.9.6 core files. Put simply, anyone using v1.0.8.5 onwards can use Queued Emails & this STOCK addon for it.