How to get the net payment amount from a paid invoice

[sofcare]

Hello,

I'm using the APIs and I've created, sent and paid for an invoice, using the Sandbox.  I'm trying to get the net payment amount that was deposited, after fees, etc.  I've found the Paypal fees amount from the Sale class, but I need the net paid amount.  I saw the field in the Pay class, but the transaction type is Sale and the Pay class didn't seem to work.  Any help would be appreciated?

Chris