In catalog/includes/classes/currencies.php
FIND:

function display_price($products_price, $products_tax, $quantity = 1) {
return $this->format($this->calculate_price($products_price, $products_tax, $quantity));
REPLACE WITH:

// BOF: MOD - EASY CALL FOR PRICE v1.4
// return $this->format($this->calculate_price($products_price, $products_tax, $quantity));

define ('CALL_FOR_PRICE_VALUE', 0);

// If you sell products for $0.00 and want to display "Call for Price!" for other products, set their price and the CALL_FOR_PRICE_VALUE to -1.
if ($products_price > CALL_FOR_PRICE_VALUE){
return $this->format($this->calculate_price($products_price, $products_tax, $quantity));
} else {
define ('TEXT_CALL_FOR_PRICE', 'TEXT_CALL_FOR_PRICE');

// You can set CALL_FOR_PRICE_TEXT to anything you want. Its style is determined by the page it is displayed on. Changes made here will be visible throughout your site.

return TEXT_CALL_FOR_PRICE;

// BOF: MOD - EASY CALL FOR PRICE v1.4
}

No file attached, only thw correction

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