hi there
have they given you a spec for the works, ie build clean, reclean, and sparkle clean ?
you need to consider the time frame that they want to comlete these works.
can be troublesome in the fact that the timeframe they give you, may in reality not be correct , as when trades slip behind, then your deadlineto finish doesnt change, so you end up, up againt it a little.
ideally you need to break it down into manageable units,
justsome thoughts for you
regards
martin