Just one question if you had to skim a 12 x 12 room and the break down is this, 1 plaster boarded ceiling, 1 x 8' wall to re-skim, 1 wall with 8' square arch so 2' on each side plus 1 foot above, 1 x 12' wall with a fire place this has already been plastered but re-skimming , 1 x 12' wall with a...