hi there
you could call the client, and say that you always visit site on the day of the start of the contract keys, alarm code etc, to ensure a smooth start.
then have a look round and see if an inital clean is required.
but back it up, show the client the areas of concern ie toilets or shelves for example.
we always quoted for an initial clean when we were quoting to win contract business, but we would quote for a whole array of serrices.
if the client wanted a cleaning service, we would highlight, windows, sanitary bins, concumables and carpet cleaning, offer the whole lot and let the client choose what they want to purchase from you.
let you become there one stop for all of their requirements., so by doing that you have control of the site, and far more difficult for the competition to get in, in the future.
regards
martin