Filter: wpd_ai_custom_product_cost_options

This filter allows developers to programmatically register custom product cost options that appear in the product edit screen.

Description

Use this filter to add custom cost types to products (beyond the standard COGS). Custom product costs can be static fees, percentages of sell price, or both combined.

Location

File:includes/functions/wpd-custom-cost-functions.php

Function:wpd_get_custom_product_cost_options()

Parameters

Return

Type: array

Description: Associative array of custom product cost options

Array Structure

array(
    'unique_slug' => array(
        'label' => 'Display Label',
        'description' => 'Helper text for admin',
        'placeholder' => '0.00',
        'static_fee' => 5.00, // Fixed amount per unit
        'percent_of_sell_price' => 10.5 // Percentage of sell price
    )
)

Example Usage

Add Packaging Cost Option

add_filter( 'wpd_ai_custom_product_cost_options', 'my_custom_product_costs', 10, 2 );

function my_custom_product_costs( $custom_costs, $product_id ) {
    // Add packaging cost option
    $custom_costs['packaging_cost'] = array(
        'label' => 'Packaging Cost',
        'description' => 'Cost of packaging materials for this product',
        'placeholder' => '2.50',
        'static_fee' => 2.50, // Default $2.50 per unit
        'percent_of_sell_price' => 0 // Not percentage-based
    );
    
    return $custom_costs;
}

Add Shipping Supplies Cost

add_filter( 'wpd_ai_custom_product_cost_options', 'add_shipping_supplies_cost', 10, 2 );

function add_shipping_supplies_cost( $custom_costs, $product_id ) {
    $custom_costs['shipping_supplies'] = array(
        'label' => 'Shipping Supplies',
        'description' => 'Boxes, tape, packing materials',
        'placeholder' => '0.00',
        'static_fee' => 3.00,
        'percent_of_sell_price' => 0
    );
    
    return $custom_costs;
}

Add Labor Cost (Percentage-Based)

add_filter( 'wpd_ai_custom_product_cost_options', 'add_labor_cost', 10, 2 );

function add_labor_cost( $custom_costs, $product_id ) {
    // Labor cost as 15% of sell price
    $custom_costs['labor_cost'] = array(
        'label' => 'Labor Cost',
        'description' => 'Assembly and quality control labor',
        'placeholder' => '0.00',
        'static_fee' => 0,
        'percent_of_sell_price' => 15.0 // 15% of sell price
    );
    
    return $custom_costs;
}

Combined Static + Percentage

add_filter( 'wpd_ai_custom_product_cost_options', 'add_fulfillment_cost', 10, 2 );

function add_fulfillment_cost( $custom_costs, $product_id ) {
    // $5 base + 3% of price
    $custom_costs['fulfillment_fee'] = array(
        'label' => '3PL Fulfillment Fee',
        'description' => 'Third-party fulfillment center fee',
        'placeholder' => '0.00',
        'static_fee' => 5.00, // $5 base fee
        'percent_of_sell_price' => 3.0 // + 3% of price
    );
    
    return $custom_costs;
}

Product-Specific Logic

add_filter( 'wpd_ai_custom_product_cost_options', 'conditional_custom_costs', 10, 2 );

function conditional_custom_costs( $custom_costs, $product_id ) {
    // Only add custom assembly cost for specific category
    $product = wc_get_product( $product_id );
    
    if ( $product && $product->is_type('variable') ) {
        // Variable products get assembly cost
        $custom_costs['assembly_cost'] = array(
            'label' => 'Custom Assembly',
            'description' => 'Required for customizable products',
            'static_fee' => 15.00,
            'percent_of_sell_price' => 0
        );
    }
    
    return $custom_costs;
}

Field Definitions

label (string, required)

Display name shown in product edit screen

description (string, optional)

Helper text displayed below the input field

placeholder (string/float, optional)

Placeholder text in the input field

static_fee (float, optional)

Fixed dollar amount added per unit. Set to null or 0 if not used.

percent_of_sell_price (float, optional)

Percentage of product sell price (0-100). Set to null or 0 if not used.

Calculation Logic

For each unit sold, the custom cost calculated as:

Cost = (Sell Price × (percent_of_sell_price / 100)) + static_fee

Example with $50 product:

• static_fee = $5
• percent_of_sell_price = 10
• Cost = ($50 × 0.10) + $5 = $10

Where Costs Appear

Once registered, custom costs:

• Appear in product edit screen (WooCommerce → Products → Edit)
• Can be set per product or per variation
• Are included in profit calculations automatically
• Show in Cost of Goods Manager
• Appear in order profit breakdowns

Best Practices

• Use unique, descriptive slugs (e.g., ‘packaging_cost’ not ‘cost1’)
• Provide helpful descriptions for store admins
• Set reasonable default values
• Use either static_fee OR percent_of_sell_price, or both
• Test with variable products to ensure compatibility

Notes

• Filter runs every time product costs are fetched
• Results are cached per product for performance
• Can register multiple custom costs (each with unique slug)
• Custom costs are optional – users can leave them blank

Related Filters

• wpd_ai_custom_product_cost_default_value– Filter default value per line item
• wpd_ai_custom_order_cost_default_value– Order-level custom costs

Related Functions

• wpd_get_custom_product_cost_options( $product_id )– Retrieve custom costs for a product
• wpd_get_additional_costs_by_product_id( $product_id )– Get calculated custom costs