I'm using a UserForm for all of this - with textboxes for
everything. I tried using a sub routine for on the change  event, but
that gives me an error when the qty is added for the first time without
a barcode  to fill in the Unit Price.

I have 8 lines on my invoice - I would like to have them added
dynamically, however, I am unsure how to do that. This is the code for
my first line in the invoice. The remaining lines are 2 - 8. I tried
using Application.Volatile (True), but that doesn't seem to change
anything.

Private Sub txtBarCode1_AfterUpdate()



Application.Volatile (True)



If IsNumeric(txtBarCode1) Then



Desc1.Text = Application.VLookup(Val(txtBarCode1.Text), _

Worksheets("Product List").Range("A:E"), 3, 0)



intUP1.Text = Format(Application.VLookup(Val(txtBarCode1.Text), _

Worksheets("Product List").Range("A:E"), 4, 0), "#,##0.00")



intTotal1.Text =
Format(Application.WorksheetFunction.Product(intQTY1, intUP1),
"#,##0.00")

txtBarCode2.SetFocus



Else



Desc1.Text = Application.VLookup(txtBarCode1.Text, _

Worksheets("Product List").Range("A:E"), 3, 0)



intUP1.Text = Format(Application.VLookup(txtBarCode1.Text, _

Worksheets("Product List").Range("A:E"), 4, 0), "#,##0.00")



intTotal1.Text =
Format(Application.WorksheetFunction.Product(intQTY1, intUP1),
"#,##0.00")



txtBarCode2.SetFocus



End If



If IsNull(intTotal1) Then

intQTY2 = ""

Else

intQTY2 = "1"

End If



Call RunningTotal



End Sub