Years ago, I used to have a buyable floor made from the image of the plywood that- by default, anyway- shows up when you use the brick foundation. It was set to $0, and was amazingly useful for when you need the floor in place to arrange furniture, but didn't want to waste money on temporary flooring or by forgetting to sell said flooring back before replacing it with a better option. There are always those stubborn bits that won't sell back from under lights, doors and furniture, as well. In one of my many purges, this floor apparently went out the window.
( So what if it's small? Some people prefer small! )