Make users accept a policy before they can use the solution - SharePoint - REST

First time a user logon to the system they should get a "policy" that they should accept. Without the accept on the policy they cannot use the solution!

I've created a custom user property on every user that I'm trying to get with REST. And if the policy is not accepted the user should get a popup (modal dialog).

JS

    $.ajax({
    url: "http://ift.tt/1EGRrQS'sp2013dev\administrator'",
    type: "GET",
    headers: { "accept": "application/json;odata=verbose" },
    success: function (data) {
        alert(JSON.stringify(data));
    },
    error: function (error) {
        alert(JSON.stringify(error));
    }

But when I'm running the query I only get a object, and cannot see any "value" only the property.

If I run the same query with "advanced rest client" (chrome extention), I get

<?xml version="1.0" encoding="utf-8"?><d:GetUserProfilePropertyFor xmlns:d="http://ift.tt/1cVQIMf" xmlns:m="http://ift.tt/1dtZymv" xmlns:georss="http://ift.tt/N7lROd" xmlns:gml="http://ift.tt/WaETtx">false</d:GetUserProfilePropertyFor>

What do I do wrong here?

Question nr 2 .. what's the best way to make users accept the policy before they can use the solution? I think that it's probably not a good way of checking a user for that property every time they open a site...

Running SharePoint 2013 Enterprise on-premise