I want to add a pet/car parking payment? How can it be done?

You can now use the the create payment button which can be found in the payments tab that displays the payments schedule. You will be able to locate the button on the top right side of the screen which once clicked will display a pop asking the necessary details about the payment, frequency, due date, date paid.

Once you enter and confirm the necessary details, these payments can be found in the payments schedule for the tenant's payment schedule that you have chosen this to reflect it in.