Instead of pulling NVP/SOAP API responses from PayPal, you can listen for the corresponding Express Checkout notifications and let PayPal push the notifications to you.
The following payment information variables contain settlement information relevant for cross-border transactions that settle in
exchange_rate- The exchange rate of a currency conversion.
settle_amount- The amount deposited into the PayPal account after a currency conversion.
settle_currency- The currency of
settlement_fee_currencycode- The currency of
settlement_fee_amt- The transaction fee associated with the payment in the settlement currency. Applicable only for use cases where the PayPal fee is charged in the settlement currency.
IPN Integration Guide - Learn more about using IPN notifications in your integration.