Yes, you can pass the Stripe processing fee to your clients. In that case, Core includes that fee in the invoice payment total when your client clicks the Pay Now button. Fees are collected immediately upon a successful transaction. As an example, you send an invoice to your client for $1000, if you choose to pass on this fee to your client, then that client has to pay $1000 + $30. Core records a payment of $1000 and deposits $1000 in your bank account. It deducts a $30 processing fee from the expense account and also adds a $30 income to the processing fee account. Check out the Stripe processing fees here.