Is there standard best practice in handling the entry of fees that are charged prior to receiving a deposit? For ex...AirBnB charges me 3% before depositing my payment.

Welcome to the Community forum, skagitsteelheadh. I'm glad to assist about recording processing fees. 

Normally, these fees are track on the deposit. Once invoice is created, manually received the payment for the whole amount and deposit it to the Undeposited Funds account.

To received the payment, here's how:

1. On the invoice, click the Receive Payment button.
2. Select the correct invoice on the Receive Payment screen.
3. In the Deposit to field, choose Undeposited Funds.
4. Click Save and close. 

To enter a bank deposit for the fee, here's what you'll need to do, 

1.  Click the Plus icon. 
2.  Select Bank Deposits.
3.  Choose the customer payments in the Select Existing Payments section.
4.  Enter the processing fee as a negative amount in the Add other funds to this deposit section.
5.  Choose the expense account that you use to track these fees in the Account drop-down.
6.  Click Save.

This method helps to ensure that customer payments and processing fees are accurately recorded. For an overview of this process, I suggest visiting this article: Enter a bank service fee while using a third-party merchant service.

Should you need further assistance with recording transactions, please let me know by commenting below. I'm always around to help you.