Sync Error: Object reference not set to an instance of an object

PROBLEM:  When syncing, you get this error message:  Object reference not set to an instance of an object.

Here is a screen shot of the error:

 

The error is with the item AFTER one listed in the sync log.
In the sync log, the last item displayed is 02 Site Work
Here's the invoice -- the error is the one after 02 Site Work, which is 04 Concrete-ahm

 

Here's how to resolve this issue.

 

STEP 1:  In QuickBooks, open the Item List by clicking Lists > Item List

 

STEP 2:  Find the item in the item list and double-click on the item to edit it.

 

STEP 3:  Look in the Cost field.  The Cost field is empty.  That is the problem.  There MUST be a value in the Cost field.

 

STEP 4:  Put a value in the Cost field and click the OK button.

 

STEP 5:  Run the sync, and it will be successful.

 

STEP 6:  You can see that the invoice was successfully synced to your QuickBooks.