diff --git a/js/app.js b/js/app.js
index 8261207..2d87e2b 100644
--- a/js/app.js
+++ b/js/app.js
@@ -31,6 +31,57 @@ function toTitleCase(str){
   return str.replace(/\w\S*/g, function(txt){return txt.charAt(0).toUpperCase() + txt.substr(1).toLowerCase();});
 }
 
+function appendPropertyData(addr) {
+  var url = '/opa-api-wrapper.php/address/' + addr;
+  var data = $.ajax(url, {
+    // dataType: 'jsonp',
+    // jsonpCallback: 'json_callback',
+    success: function (res) {
+      res = jQuery.parseJSON(res);
+      // the property listing from api.phillyaddress is loaded with information.
+      // At this point i'm only interested in assessed value per square foot, 
+      // but there's loads more data here that could be included in the listing. 
+      var property = res.property.account_details;
+      var tax = res.property.valuation_details;
+      var land_sqft = parseFloat(property.land_area.replace(' SqFt', ''));
+      var bldg_sqft = parseFloat(property.improvement_area.replace(' SqFt', ''));
+      var land_ass_2013 = parseInt(tax[2013].assessed_land_exempt.replace(/[$,]/gi, '')) + parseInt(tax[2013].assessed_land_taxable.replace(/[$,]/gi, ''));
+      var land_ass_2014 = parseInt(tax[2014].assessed_land_exempt.replace(/[$,]/gi, '')) + parseInt(tax[2014].assessed_land_taxable.replace(/[$,]/gi, ''));
+      var bldg_ass_2013 = parseInt(tax[2013].assessed_improvement_exempt.replace(/[$,]/gi, '')) + parseInt(tax[2013].assessed_improvement_taxable.replace(/[$,]/gi, ''));
+      var bldg_ass_2014 = parseInt(tax[2014].assessed_improvement_exempt.replace(/[$,]/gi, '')) + parseInt(tax[2014].assessed_improvement_taxable.replace(/[$,]/gi, ''));
+      
+      var land_sqft_2013 = Math.floor(land_ass_2013 / land_sqft);
+      var land_sqft_2014 = Math.floor(land_ass_2014 / land_sqft);
+      var bldg_sqft_2013 = Math.floor(bldg_ass_2013 / bldg_sqft);
+      var bldg_sqft_2014 = Math.floor(bldg_ass_2014 / bldg_sqft);
+      var land_delta = 0;
+      var bldg_delta = 0;
+
+      land_delta = Math.floor((land_sqft_2014 / land_sqft_2013) * 100);
+      if (land_sqft_2013 > land_sqft_2014) {
+        land_delta = -(100 - land_delta);
+      }
+
+      bldg_delta = Math.floor((bldg_sqft_2014 / bldg_sqft_2013) * 100);
+      if (bldg_sqft_2013 > bldg_sqft_2014) {
+        bldg_delta = -(100 - bldg_delta);
+      }
+      $('#tooltip #opa-data-container').html(
+          '<strong>OPA Data</strong>' +
+            '<br>improvement area: ' + property.improvement_area +
+            '<br>land area: ' + property.land_area + 
+            '<br>2013 improvement value / sqft: $' + bldg_sqft_2013 +
+            '<br>2014 improvement value / sqft: $' + bldg_sqft_2014 +
+            '<br>% change: ' + bldg_delta + '%' + 
+            '<br>2013 land value / sqft: $' + land_sqft_2013 +
+            '<br>2014 land value / sqft: $' + land_sqft_2014 +
+            '<br>% change: ' + land_delta + '%'
+          );
+    }
+  });
+  $('#tooltip').append('<br><span id="opa-data-container">acquiring OPA data...</span>');
+}
+
 // Create the map
 app.initMap = function(callback) {
   var mapSettings = app.mergeMapSettings();
@@ -55,10 +106,12 @@ app.initMap = function(callback) {
                               "2013 Tax: $" + Number(o.data.tx_2013).formatMoney() + "<br>" +
                               "2014 Market Value: $" + Number(o.data.mktval_14).formatMoney() + "<br>" +
                               "2014 Tax: $" + Number(o.data.tx_2014).formatMoney() + "<br>" +
-                              "Change in Tax: " + Number(o.data.tax_change * 100).toFixed(0)  + '%';
+                              "Change in Tax: " + Number(o.data.tax_change * 100).toFixed(0)  + '% ' + // Append property data on a time callback, so that we're not hammering the data api server:
+                              '<script type="text/javascript">clearTimeout(app.myInterval); app.myInterval = setTimeout(function() { appendPropertyData("' + o.data.address + '") }, 1000); </script>';
 
 
               if ($('#tooltip').length) {
+                window.clearTimeout(mapSettings.myTimeout);
                   $('#tooltip').html(contents).show();
               } else {
                 $('<div/>', {
@@ -71,7 +124,7 @@ app.initMap = function(callback) {
 
               $(document).mousemove(function(e){
                 var posX = e.pageX - offset.left - 130;
-                    posY = e.pageY - offset.top - 150;
+                    posY = e.pageY - offset.top - 300;
 
                 $('#tooltip').css({ left: posX, top: posY });
               });
diff --git a/opa-api-wrapper.php b/opa-api-wrapper.php
new file mode 100644
index 0000000..51031d8
--- /dev/null
+++ b/opa-api-wrapper.php
@@ -0,0 +1,15 @@
+<?php
+// Quick and dirty cross-domain workaround for api.phillyaddress.com server.
+$request = $_SERVER['REQUEST_URI'];
+$request = str_replace('/opa-api-wrapper.php', 'http://api.phillyaddress.com/', $request);
+if (!function_exists('curl_init')){
+    die('Sorry cURL is not installed!');
+}
+$ch = curl_init();
+curl_setopt($ch, CURLOPT_URL, $request);
+curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
+curl_setopt($ch, CURLOPT_TIMEOUT, 10);
+$output = curl_exec($ch);
+curl_close($ch);
+echo $output;
+