Rental Hire Creating a Negative Charge

I am trying to extend a Hire the additional charge shows a negative rate.

Solution

This is because the New/Extended Details Hire Period have had the Terms changed from the existing Hire Period to a lesser rate eg Month to Week or Week to Hour.

The addition charge will always be a credit if the Hire Period is changed to be less than the original Hire Period.  If this is the case it is recommended that a new Hire is set up.