Visual Basic.NET - Realizar filtro de un Select donde la tabla contiene datos numericos

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

    Dim ds1 As New DataSet

    Dim dt1 As New DataTable

    Dim Fechini As Date

    Dim Fechfin As Date

    Fechini = Date.FromOADate(Val(DateTimePicker1.Value))

    Fechfin = Date.FromOADate(Val(DateTimePicker2.Value))

    Dim adp1 As New OleDb.OleDbDataAdapter("SELECT a.guia, a.consignatario, a.fechaarrivo, a.valor, b.fechanotif from Manifiesto a left outer join notifimpuestos b on a.guia = b.guia where a.valor >=  ' & TextBox2.Text & ' and a.fechaarrivo between ('" & Fechini & "') AND ('" & Fechfin & "')", conn)

    Try

        ds1.Tables.Add("tabla")

        adp1.Fill(ds1.Tables("tabla"))

        Me.DataGridView1.DataSource = ds1.Tables("tabla")

    Catch ex As Exception

        MsgBox(ex.ToString)

    End Try

Dim Cmd as new OLedbCommand

Cmd.CommandText="SELECT a.guia, a.consignatario, a.fechaarrivo, a.valor, b.fechanotif from Manifiesto a left outer join notifimpuestos b on a.guia = b.guia where a.valor >=@Valor and a.fechaarrivo>=@Fechini AND a.fechaarivo<=@Fechfin "

Cmd.CommandType=CommandType.Text

Cmd.Parameters.Add("@Valor",OledbType.Decimal).Value=Convert.toInt32(txtvalor.text)

Cmd.Parameters.Add("@Fechini",OledbType.Date).value=Fechini

Cmd.Parameters.Add("@Fechfin",OledbType.Date).Value=Dechfin

Dim  adap as = new OleDBDataAdapter()

custDA.SelectCommand = selectCMD

Conn.Open();

Dim custDS as new DataSet()

custDA.Fill(custDS, "tabla")