WC Vendors Pro - Commission Rate depending on how much a product sells for

functions.php

/* WC Vendors Pro -- No % for commission, just a tiered fee structure */
add_filter( 'wcv_commission_rate', 'my_wcv_commission_rate', 10, 5 );
function my_wcv_commission_rate( $commission, $product_id, $product_price, $order, $qty ) {
	
	// First, reduce price to qty1 to do calculations
	$product_price = $product_price / $qty; 
        
        // Second, run through the price and apply the right commission fee
        if ( $product_price > 48.99 ) { 
        	$commission_fee = 3.36; 
        } elseif ( $product_price >= 42.00 && $product_price <= 48.99 ) { 
        	$commission_fee = 2.94; 
        } elseif ( $product_price >= 35.00 && $product_price <= 41.99 ) { 
        	$commission_fee = 2.52; 
       	} elseif ( $product_price >= 28.00 && $product_price <= 34.99 ) { 
       		$commission_fee = 2.10; 
       	} elseif ( $product_price >= 21.00 && $product_price <= 27.99 ) { 
       		$commission_fee = 1.68; 
       	} elseif ( $product_price >= 14.00 && $product_price <= 20.99 ) { 
       		$commission_fee = 1.26; 
       	} elseif ( $product_price >= 7.00 && $product_price <= 13.99 ) { 
       		$commission_fee = 0.84; 
       	} elseif ( $product_price >= 0.00 && $product_price <= 6.99 ) { 
       		$commission_fee = 0.42; 
       	}
        
        // Third, set the commission to price - fee, since this is just a
        // deduction no percentages are applied
        $commission = $product_price - $commission_fee; 
        
        // Fourth, play it safe by setting to 0 if it's negative
        if ( $commission < 0 ) $commission = 0;
        
        // Fifth, round it so there's no half pennies
        $commission = round( $commission * $qty, 2 );
        
        // Finally, return the commssion total per product.
        return $commission;
}