Living Room/Dining Room

Our realtor thought we should move the piano but I honestly don't know if we will be able to do that before putting the house on the market. When I showed the house to her, I had the big brown chair up against that window, right next to the piano, so I think it just looked really cluttered. What do you think...

...which leads me back to the thought of selling these monstrous chairs. It is a small room and I'm worried that these really highlight how small the room is. However, we don't have any other chairs to take their place, so I don't know....thoughts?

 Also, mantel decor! I'm so bad with mantels! It is a pretty narrow mantel as well.

Here is this space without the chair. If I do remove the chair, I'm not sure if I need something else here or not.

When my realtor looked through the house I had a big black mirror on this wall and she thought it was good like that. Then the mirror sort of fell off. It isn't broken or anything so I'm not sure if I should try and rehang it. I also have a lot of lighting issues in this room.

Realtor did not like my family picture collage as the main focal point on this wall so I need to replace it with some kind of art. I do have a gift card to World Market that I might use for this purpose. Also, the wine rack. I have some glass jars that I usually keep in there. Not sure how to style it.