Normally, stairway $5.00 per step, floor $5.00 per sqaure yard. As the carpeter itself depening the quality you like. Also, for the floor footage, you need add roughly 10% extra as you need to cut and through some carpeter. + b$ u3 d1 F7 T( w * T* o8 p( u0 I" `This is just rough idea.