if (list_updated('stock_id')) {
    $Ajax->activate('price_table');
    $Ajax->activate('price_details');
}
if (list_updated('stock_id') || isset($_POST['_curr_abrev_update']) || isset($_POST['_sales_type_id_update'])) {
    // after change of stock, currency or salestype selector
    // display default calculated price for new settings. 
    // If we have this price already in db it is overwritten later.
    unset($_POST['price']);
    $Ajax->activate('price_details');
}