I agree... it's an Aero Flite. This particular trailer was the second one the company built (serial number 102X) and was unveiled to the public in December 1945. I have been researching the company for the past several years after buying an Aero Flite from Rob Baker via this forum. I think it is very possible the lady in the window was Connie Hussey, the daughter of the gentleman who started the company (she became half owner later).
The first Aero Flite (serial number 101X) was actually owned by Wally Byam for a brief period during 1947. He had purchased it from Cornelius Vanderbilt, Jr. I think Wally took it on a trade when Vanderbilt bought a new Airstream. Wally and Vanderbilt toured Europe in
1948 in Airstreams and I believe Vanderbilt traded in the Aero Flite on a new Airstream. My wife and I bought Aero Flite 101X in June 2006 and obtained original ownership documents with it showing the history.
I built my wife a scale model of the trailer for Christmas (she really wanted a bird house). Here's a photo (if I do this correctly) at approximately the same angle as the trailer in the old time photo.