I think this is what you wanted


Option Explicit
Sub InsertPricePoints()
    Dim aryPoints As Variant
    
    aryPoints = Array(0, 500, 800, 1000, 1500, 2000, 2500, 3000, 3500, 4000, 4500)
    
    Dim iRow As Long
    
    Application.ScreenUpdating = False
    
    With ActiveSheet
        For iRow = .Range("B3").CurrentRegion.Cells(1, 1).End(xlDown).Row To .Range("B3").Row + 1 Step -1
            If Application.WorksheetFunction.Match(.Cells(iRow, 2).Value, aryPoints, 1) <> Application.WorksheetFunction.Match(.Cells(iRow - 1, 2).Value, aryPoints, 1) Then
                .Rows(iRow).Insert Shift:=xlDown, CopyOrigin:=xlFormatFromLeftOrAbove
            End If
        Next iRow
    End With
    Application.ScreenUpdating = True

End Sub