Hello Everyone

I thought i would be interested in getting new wood flooring but once i looked at the floor at the i realize i didn't want that.
I currently have wood flooring now. which was here when i brought the house. I was told by a contractor that my floors are 1/4 and he don't recommend sanding them.

I need to know is that true? I would rather lightly sand and polish.

I have a black spot on the floor and a few long dark scratches and it is NO SHINE what so ever.