AddNewCol

'Alternative single line dynamic code
'Code will add column to the left of the address, taking right cells as format
'A1 is the address of the cell to start adding columns to
'3  is the number of columns to add
[A1].Resize(, 3).EntireColumn.Insert
Cells(1, 1).Resize(, 3).EntireColumn.Insert

'Call Method :
a = addNewCol("A1", True)
'where a returns the address of the newly added column

Public Function addNewCol(ByVal targAdd As String, Optional bLeftAdd As Boolean = False) As String

'this function adds a column to the left or right the target address provided, depending on the boolean flag indicator

If bLeftAdd <> True Then
    'insert a column to the right of the cell
    ActiveSheet.Range(targAdd).EntireColumn.Offset(0, 1).Insert
    addNewCol = Range(targAdd).Offset(0, 1).Address
Else
    'insert a column to the left of the cell
    ActiveSheet.Range(targAdd).EntireColumn.Insert
    addNewCol = Range(targAdd).Address
End If

End Function