In many occasions, a property manager has to collect a guest payment outside of the system, like a check or even cash. In this case, there is a way to inform Hostfully to adjust the balance due for this booking, by recording the payment already made:
From the Pipeline screen, find the particular booking (you can also use the search field)
Mouse over the booked circle and select "Record a Payment"
When the pop-up window shows up, enter an amount in the field and click "Add"
When you look at the Order page for this booking, you will see the amount you entered will be reported as a "manual transaction", and the balance for this reservation will be adjusted accordingly.