We have only Lightly dusted. I have not tried to slide the easel adjustment.
I will leave that to the new owner. Approximate height when laying flat in picture:15 3/4. 8 across at widest part across top. Easel bottom footprint measures approximately: 5.5" x 6.5". Opening that would hold advertising card does not run parallel to bottom and has a slight angle to the design.
(Lower on left side and goes up on right) it is hard to say if possibly misaligned or it may be original to the design. Would look amazing as a menu holder at a restaurant or a invitation or directions board at a event. Possibly could work (with some additional support) to show a special book, picture, mirror or piece of music. Early Hard to find item.