I had a contractor install some Trex fascia board (1x12) on my deck. He and his partner used a flat head deck screw to fasten. Of course there was mushrooming at each site. So, to smooth out the mushrooming material, they sanded it lightly . Only problem is that there are now white dull marks everywhere. Can this be improved on, buffed out, etc. I think that this guy should apply all new boards. Any opinions? Also, wouldn't it look better if the fascia was predrilled and perhaps galvanized finish nails used for attaching? [sad]