[difurios]

бездействует

var radio = document.getElementById("radio");
			var radio2 = document.getElementById("radio2");
			var radio3 = document.getElementById("radio3");
            var count = document.getElementById("count");
            var result = document.getElementById("result");
            var price = 0;
			radio.checked && (price += parseInt(radio.value));
			radio2.checked && (price += parseInt(radio2.value));
			radio3.checked && (price += parseInt(radio3.value));
	    price += parseInt(count.value) * parseInt(result.value);
            result.value = price;

<input type="radio" name="radio" id="radio" value="2830"onClick="show_visibility('Dop')">
        <label for="radio"></label>
        <input type="radio" name="radio" id="radio2" value="2810"onClick="show_visibility('Dop')">
        <input type="radio" name="radio" id="radio3" value="1800"onClick="toggle_visibility('Dop')">