Hi think this should help. You can change which cell gets ticked 

Private Sub Worksheet_BeforeDoubleClick(ByVal Target As Range, Cancel As Boolean)
Dim SerialNo As String 'declare as string
If Not Intersect(Target, Range("I11:I2010")) Is Nothing Then
    'with application inputbox, use could use a type of 1 to ensure a number
    'but this would overflow if a number over 32768 was entered.
    SerialNo = Application.InputBox("Please enter Serial")
    If SerialNo = False Then
        'user cancelled
    ElseIf Not IsNumeric(SerialNo) Or SerialNo > 32768 Then
        'invaid number
        MsgBox "Enter a valid number"
    Else
        With Sheets("Lost Property Log")
            'search log
            .Unprotect
            'change the serialNo to integer for the match
            fRow = Application.Match(CInt(SerialNo), .Columns(3), 0)
            If Not IsError(fRow) Then
                'add the value
                .Cells(fRow, 9).Value = Cells(Target.Row, 9).Value
                'set the tick
                If ActiveCell.Value = ChrW(&H2713) Then
                    ActiveCell = ""
                Else
                    ActiveCell.Value = ChrW(&H2713)
                End If
            Else
                'not found in log
                MsgBox "Serial # not found in log"
            End If
            .Protect
        End With
    End If
End If
End Sub