var $text = $('#extra_service_page'),
$box = $('.my-checkbox');
$box.on('click', function() {
var values = [],
sum = 0;
$box.filter(':checked').each(function() {
values.push(this.value);
sum += parseInt($(this).siblings('div[data-price]').data('price'));
});
$('.sum_all').text(sum);
$text.val(values.join(','));
});