Hi. We used P120 grade with mouse sander, got through a few discs! Then washed down with clean water (no chemicals), let it dry out for 24 hours and just using a mini foam roller painted it with Dulux weather shield multi surface paint for pvc, metal and wood, no undercoat needed, took 3 coats for the finish. Let it dry between coats. Very happy with the results. Might start this as a part time job..