problema de ventas

Private Sub cantidad_lostfocus(Index As Integer)

If precio(Index) = "" Then
    importe(Index) = ""
   
    Else
   
    If cantidad(Index) <> "" Then
        importe(Index) = precio(Index) * cantidad(Index)
       
    End If
    End If
   

End Sub

Private Sub Command1_Click()

total = 0
For i = 0 To 7
If importe(i) = "" Then
total = total + 0
Else
total = total + importe(i)
End If
Next i
Text1.Text = total

End Sub

Private Sub Command2_Click()
End

End Sub

Private Sub List1_Click()

If List1.Selected(List1.ListIndex) Then
    Select Case List1.ListIndex
   
    Case 0
   
        precio(0).Caption = Format(5, "fixed")
       
    Case 1
   
        precio(1).Caption = Format(4, "fixed")
       
    Case 2
   
        precio(2).Caption = Format(0.5, "fixed")
       
    Case 3
   
        precio(3).Caption = Format(1.5, "fixed")
       
    Case 4
   
        precio(4).Caption = Format(1, "fixed")
       
    Case 5
   
        precio(5).Caption = Format(2, "fixed")
   
    Case 6
   
        precio(6).Caption = Format(2.5, "fixed")
       
    Case 7
   
        precio(7).Caption = Format(3, "fixed")
       
    End Select
   
    Else
        precio(List1.ListIndex) = ""
        cantidad(List1.ListIndex) = ""
        importe(List1.ListIndex) = ""
       
    End If
   
End Sub

Private Sub Option1_Click(Index As Integer)

If Option1(0).Value = True Then
Option1(1).Value = False

Text2.Text = Text1.Text
Else
Option1(0).Value = False
Text2.Text = Text1.Text * 1.1
End If

End Sub