opening an additional workbook from another workbook then resizing the newly opened book

I have a workbook that users need to open another "Calculator" workbook to enter data to calculate mortgate payouts
what i would like to see happen is while they aere in the main workbook they click a button and the "CALCULATOR" workbook pops up and they do the calculation
and the result is returned to a specific cell in the "MAIN" work book ...is this possible. here is what i have so far just opening the "CALCULATOR" workbook

Sub Button1_Click()
Dim strFilePath As String
Dim xlApp As Object
Set wb1 = ActiveWorkbook
'MsgBox (ActiveWorkbook.Path)
strFilePath = ActiveWorkbook.Path & "\Calculators\Closed Mortgage Penalty Calculator.xlsx"

Set xlApp = CreateObject("Excel.Application")
xlApp.Visible = True
xlApp.Workbooks.Open strFilePath
xlApp.Left = 100
xlApp.Top = 1
xlApp.Width = 400
xlApp.Height = 400
xlApp.Worksheets("Sheet1").Range("A60").Activate
xlApp.ExecuteExcel4Macro "Show.ToolBar(""Ribbon"",False)"
' xlApp.Worksheets("Sheet1").Range("C63").Copy
End Sub



what I would Like to have happen is fire off the
xlApp.Worksheets("Sheet1").Range("C63").Copy

code so that the result of the calculation is saved to the windows clipboard when the external "CALCULATOR"
workbook is closed ...can that be done the "MAIN" workbook detect what is happening on the child "CALCULATOR" workbook?

Have you considered a "calculator" worksheet in the main workbook that you show\hide as needed? Or a "calculator" userform? Those two methods are more common than opening\closing a seperate workbook.