JSON, jQueryUI Autocomplete, AJAX - Cannot get data when array is not local - ajax

Question

I have searched stackoverflow, as well as the web for some insight into how to get the jQueryUI Autocomplete plugin working with my JSON data, and I'm at a loss. I had it working like a charm with a local data array. I was able to pull values and build html.
I ran into a problem when I had to pull JSON form this source:
/Search/AjaxFindPeopleProperties2
?txtSearch=ca pulls up the test data that I am trying to loop through, when I type in 'ca' to populate the autocomplete list. One of the problems is that ?term=ca is appended to the url instead of ?txtSearch=ca and I'm not sure how to change it.
This is an example of the data:
{
"MatchedProperties": [
{
"Id": 201,
"Name": "Carlyle Center",
"Description": "Comfort, convenience and style are just a few of the features you'll ...",
"ImageUrl": "/Photos/n/225/4989/PU__ThumbnailRS.jpg"
}
]
}
...and here is the ajax call I'm trying to implement:
$(document).ready(function () {
val = $("#txtSearch").val();
$.ajax({
type: "POST",
url: "/Search/AjaxFindPeopleProperties2",
dataType: "json",
data: "{}",
contentType: "application/json; charset=utf-8",
success: function (data) {
$('#txtSearch').autocomplete({
minLength: 0,
source: data.d, //not sure what this is or if it's correct
focus: function (event, ui) {
$('#txtSearch').val(ui.item.MatchedProperties.Name);
$.widget("custom.catcomplete", $.ui.autocomplete, {
//customize menu item html here
_renderItem: function (ul, item) {
return $("<li class='suggested-search-item" + " " + currentCategory + "'></li>")
.data("item.autocomplete", item)
.append($("<a><img src='" + item.MatchedProperties.ImageUrl + "' /><span class='name'>" + item.MatchedProperties.Name + "</span><span class='location'>" + "item.location" + "</span><span class='description'>" + item.MatchedProperties.Description + "</span></a>"))
.appendTo(ul);
},
_renderMenu: function (ul, items) {
var self = this,
currentCategory = "Properties Static Test Category";
$.each(items, function (index, item) {
if (item.category != currentCategory) {
ul.append("<li class='suggested-search-category ui-autocomplete-category'>" + currentCategory + "</li>");
//currentCategory = item.category;
}
self._renderItem(ul, item);
});
}
}//END: widget
//return false;
},
select: function (event, ui) {
$('#txtSearch').val(ui.item.MatchedProperties.Name);
//$('#selectedValue').text("Selected value:" + ui.item.Abbreviation);
return false;
}
});
},
error: function (XMLHttpRequest, textStatus, errorThrown) {
alert(textStatus);
}
}); //END ajax
}); //END: doc ready
and I'm initializing here:
<script type="text/javascript">
//initialize autocomplete
$("#txtSearch").autocomplete({ //autocomplete with category support
/*basic settings*/
delay: 0,
source: "/Search/AjaxFindPeopleProperties2",
autoFocus: true,
minLength: 2 //can adjust this to determine how many characters need to be entered before autocomplete will kick in
});
//set auto fucus
$("#txtSearch").autocomplete("option", "autoFocus", true);
</script>
any help would be great...
Thanks!