var limit = 3;
$('input.single-checkbox').on('change', function(evt) {
if($(this).siblings(':checked').length >= limit) {
this.checked = false;
}
});(function ($) {
$(document).ready(function () {
$(document).on("change", ".pricing-levels-3 input", function () {
var numberOfChecked = $(".pricing-levels-3 input:checkbox:checked").length;
if (numberOfChecked >= 2) {
$(".pricing-levels-3 input:not(:checked)").prop("disabled", true);
} else {
$(".pricing-levels-3 input:not(:checked)").removeAttr("disabled", true);
}
});
});
})(jQuery);