Add Item And Total In Textboxes?

I'm making a simple program. It is almost finish in a manner of simple function. But I have problems related to "Add item and total in textboxes".

In this simple program:-

1. User select the item.

2. User select the quantity.

3. User click the Add Item button.

4. Then to add more items, follow step 1-3 and price will appear in the textboxes on the right.

3. Total textbox will show the total price of 5 selections.

The problems are:

1. how to make second-five selection appear without interrupting other text box.

2. how to show total of all five selections

This below is the codes I use "when user click the stop button". But I got most of above problems...

Public Class Form2
Private Sub AddButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles AddButton.Click
Dim total As Double

[Code]....