I am creating an invoice table for the customers. Sometime they will have to send me the commission fees or sometime I send them fees (account balance). How to design a invoice table in this situation?

I have came up with this solution, im not sure if this is correct or what is the alternative way?

Code:
tbl_invoice
- invoice_id (PK)
- order_id (FK)
- invoice_date
- amount (copy the price from tbl_order.total table)
- status (Invoice Sent, Cancelled, Amount Received, Amount Sent)


tbl_Payments
 - invoice_id (FK)
 - amount_received (recieved commission fees from customer)
 - amount_sent (sent fees to customer)
 - date_received
 - date_sent
if the tbl_invoice.amount is -30.00 that mean customer will send me the fees.

if the tbl_invoice.amount is 30.00 then I will send the customer the fees.

Do I need tbl_invoice.amount field?