The cost of sanding a floor depends on the size of the area to be sanded-larger area to be sanded results in a higher cost. Secondly, it depends on the type of floor. Sanding hardwood floors, for example, are more time-consuming and expensive than sanding soft flooring. Last but not the least, the cost of sanding a floor depends on ​your locality as urban areas mean higher labour costs, which add up to the overall costing. The same criteria apply to polyurethane floors too.