Antique Hall Tree Mirror

I am trying to get more information on this piece.  I am downsizing and thinking about selling it.  I would  like to know more before I do. I really don't know anything about it except for it's a beautiful piece.  The size is 82" height x 24" wide x 10" depth. There is no writing or anything printed on the back.  It was passed down from my Grandfather and as far as I know it was passed down to him.  Years ago I had an antique dealer look at it and he said it was late 1700 early 1800.  Any information I can get is appreciated.  Thanks

J