Option Explicit
Private e As Variant

Private Sub usloviya()
Dim n As Integer, a As String, b As Integer, z As Integer, i As Integer, x As Integer
n = Lst1.ListCount - 1
z = 0
x = 0
If Lst1.ListCount = 0 Then
   cmdDel.Enabled = False
   cmdCus.Enabled = False
   cmdAdd.Enabled = True
Else
For i = 0 To n
  a = Lst1.List(i)
  b = Lst2.List(i)
   If b >= 170 Then
     Lst3.AddItem ("Подходит")
     x = x + 1
   Else
     Lst3.AddItem ("Не подходит")
   End If
Next i
End If
lbl.Caption = x
cmdAdd.Enabled = True
cmdDel.Enabled = True
cmdCus.Enabled = True
End Sub

Private Sub cmdAdd_Click()
Dim a As String, b As Integer, i As String
On Error GoTo m
Do
  a = InputBox("Введите фамилию", "Ввод")
  b = InputBox("Введите рост", "Ввод")
  Lst1.AddItem (a)
  Lst2.AddItem (b)
  i = MsgBox("Добавить еще?", vbOKCancel, "Ввод")
Loop While i = vbOK
Call usloviya
Exit Sub
m:
  MsgBox "Ошибка ввода данных", vbCritical, _
  "Error"
End Sub

Private Sub cmdDel_Click()
Dim v As String
'If Lst1.ListIndex <> -1 Then
  v = MsgBox("Удалить?", vbOKCancel, "Удаление")
   If v = vbOK Then
     Lst1.RemoveItem (e)
     Lst2.RemoveItem (e)
     Lst3.RemoveItem (e)
     Call usloviya
   Else
     Lst1.ListIndex = -1
   End If
cmdAdd.Enabled = True
cmdDel.Enabled = False
cmdCus.Enabled = False
'End If
End Sub

Private Sub cmdCus_Click()
Dim m As String, a As String, x As Integer, f As String
If MsgBox("Заменить фамилию?", vbOKCancel, "Замена") = vbOK Then
  a = InputBox("Введите Фамилию", "Замена")
  Lst1.RemoveItem e
  Lst1.AddItem a, e
End If
If MsgBox("Заменить рост?", vbOKCancel, "Замена") = vbOK Then
  x = InputBox("Введите рост", "Замена")
  Lst2.RemoveItem e
  Lst2.AddItem x, e
End If
Lst1.ListIndex = -1
Lst2.ListIndex = -1
Lst3.ListIndex = -1
Call usloviya
cmdAdd.Enabled = True
cmdDel.Enabled = False
cmdCus.Enabled = False
End Sub

Private Sub Form_Load()
If Lst1.ListCount = 0 Then
cmdAdd.Enabled = True
cmdDel.Enabled = False
cmdCus.Enabled = False
End If
End Sub

Private Sub Lst1_Click()
e = Lst1.ListIndex
Lst2.ListIndex = e
Lst3.ListIndex = e
cmdAdd.Enabled = False
cmdDel.Enabled = True
cmdCus.Enabled = True
End Sub