title: Posting Quickbooks Online invoice without using CustomerRef
body: <p>How do I create an invoice in QBO without using the CustomerRef field? Every example just shows:</p>
  
  <pre><code>&lt;CustomerRef name="ACME Inc"&gt;2&lt;/CustomerRef&gt;
  </code></pre>
  
  <p>Do I ALWAYS have to look up the Id? Can't I just post to "ACME Inc" without finding the ref # (2)? The older QBXML did this no problem.</p>
  
  <p>Similarly for items, they all have it like this:</p>
  
  <pre><code>&lt;ItemRef name="Hours"&gt;2&lt;/ItemRef&gt;
  </code></pre>
  
  <p>How do I just specify "Hours" and have QB look it up for me?</p>