Hello,

I am new to Javascript and I am working on an exercise I found on a website.
The problem is that my loops will not update the running total values in these functions I am keeping. I have having a hard time finding where the error is occuring and your help is appreciated.

Code:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>Untitled Document</title>

</head>
<body>
<h1>Configure Your GT Super Sportscar</h1>
<form id="orderform" action="#">
<table border="1">

<tr>

<td><input type="radio" name="manual" checked="checked" id="manual" value="17790.00" />GT Manual</td><td>$17,790.00</td> 
</tr>
<tr>
<td><input type="radio" name="manual" id="auto" value="18590.00" />GT Automatic</td><td>$18,590.00</td>
</tr>
<tr>
<td><input type="radio" name="manual" id="smanual" value="22455.00" />GT-S Manual</td><td>$22,455.00</td>
</tr>
<tr>
<td><input type="radio" name="manual" id="sshift" value="23155.00"/>GT-S Sportshift</td><td>$23,155.00</td>
</tr>
</table>
<table border="1">

<tr>
<td><input type="radio" name="manual" id="combo1" value="1235.00" />Option Combo #1</td><td>$1235.00</td>
</tr>
<tr>
<td><input type="radio" name="manual" id="combo2" value="3354.00" />Option Combo #2
<ul>
<li>Rear Spoiler and Fog Lamps</li>
<li>Keyless Entry</li>
<li>Power Tint and Side Moonroof</li>
<li>Power Windows, Doors, and Cruise Control</li>
</ul>
</td>
<td>$3354.00</td>
</tr>
<tr>
<td><input type="radio" name="manual" id="nocombo" value="0" />No Combo</td><td>$0</td>
</tr>

</table>
<table border="1">

<tr>

<td><input type="checkbox" name="amen" id="cac" value="550.00"/>CD Autochanger</td><td>$550.00</td> 
</tr>
<tr>
<td><input type="checkbox" name="amen" id="vss" value="399.00"/>VIP Security System</td><td>$399.00</td>
</tr>
<tr>
<td><input type="checkbox" name="amen" id="adm" value="295.00"/>Auto Dimming Mirror</td><td>$295.00</td>
</tr>

</table>
<table border="1">

<tr>
<td><input type="text" name="price" id="price" /></td><td><input type="button" onclick="showit()" value="Calculate Total" /></td>
</tr>
</table>
</form>
<script type="text/javascript">
/**
* @author Isaac's
*/
function getval(){
var options = document.forms["orderform"].manual;
var optionslength = options.length;
var total = 0;
for (var i = 0; i &lt; optionslength; i++) {
if (options[i].checked) {
options[i].value += total;
}
return total;
}
}
var result1 = getval();
function getval2(){
var total=0;
var checkboxes = document.forms["orderform"].amen;
for (var i = 0; i &lt; checkboxes.length; i++) {
checkboxes[i].value += total;
}
return total;
}

var result2 = getval2();

function showit(){
var total = parseFloat(result1) + parseFloat(result2)
alert(total);
}

</script> 
</body>
</html>