[рони]

Foknik,

<script>
    $(function() {
    function calc() {
        var $select = +$("select#select option:selected").data("service");
        var $price_2 = $("input#check_2:checked").length ? +$("input#check_2:checked").data("price") : 0;
        var $price_3 = $("input#check_3:checked").length ? +$("input#check_3:checked").data("price") : 0;
        var $final_prise = $select + $price_2 + $price_3;
        $("span#total").text($final_prise)
    }
    $("select#select, input#check_2, input#check_3").change(calc)
});
  </script>