Service/Sale/Payment.php
private function validateCustomerBalance($balance, $amount, $useDelta = false)
    {
        if ($useDelta) {
            $result = (($balance + self::CONVERSION_DELTA) >= $amount);
        } else {
            $result = ($balance >= $amount);
        }
        return $result;
    }
private function validateCustomerBalance($balance, $amount, $useDelta = false)
    {
        if ($useDelta) {
            $result = (($balance + self::CONVERSION_DELTA) >= $amount);
        } else {
            $result = ($balance >= $amount);
        }
        return $result;
    }
private function validateCustomerBalance ( $ balance , $ amount , $ useDelta = false ) { if ( $ useDelta ) { $ result = ( ( $ balance + self :: CONVERSION_DELTA ) >= $ amount ) ; } else { $ result = ( $ balance >= $ amount ) ; } return $ result ; }
Customer balance should be greater or equal to transaction amount.

@param float $balance
@param float $amount
@param bool $useDelta use some delta in values comparison (currency conversion gap)
@return bool
Customer balance should be greater or equal to transaction amount .